共查询到20条相似文献，搜索用时 31 毫秒
1.
在4-氨基吡啶、4-吡啶甲胺分子上分别修饰丁二酸酐得到构筑超分子组装体的结构单元,选择均苯三甲酸作为配对小分子,成功合成了4-氨基吡啶、4-甲氨基吡啶与均苯三甲酸的双组份超分子水凝胶.最小胶凝浓度分别为23、35 mg/mL,在凝胶聚集体中,双组份凝胶剂聚集成带状或纤维状的聚集体,分子间氢键和π-π相互作用是形成自组装水凝胶的主要驱动力. 相似文献
2.
Oil spills result in tremendous damage to the environment and ecosystem.In this study,several p-alkoxybenzoyl-based gelators (1,2a,2b,2c,3) synthesized from commercially available materials were designed for recovering oil from an oil-water mixture.Gels with remarkable gelation ability in various oils were characterized by nuclear magnetic resonance,Fourier transform infrared spectroscopy and X-ray diffraction to study the driving forces of self-assembly.Notably,these gelators could achieve the goal of recycling oil from the oil-water mixture at room temperature.In addition,gelator 2b could be used to remove toxic dyes from aqueous solutions with high efficiency.Therefore,these compounds were considered promising materials for oil spill recovery and dye removal due to their practicality and high efficiency. 相似文献
3.
TheadventofstrongandtoughZrO2 basedce ramicshasgeneratedconsiderablescientificandtech nologicalinterestinthisclassofstructuralceram ics[1—3]. Nowfine grainedsinteredceramicscanbeproducedusingcommerciallyavailableultrafinepow ders,whichcanbesinteredtofulldensityatrelativelylowtemperatures. High qualityZrO2 powderisvitalforthesuccessfuldevelopmentofadvancedZrO2 ce ramics. Severalwetchemicalmethodshavebeende velopedforpreparationofsuchhigh purity, homoge neousandsinterableceramicspowders,… 相似文献
4.
欧光川 《湖南科技学院学报》2005,26(5)
Hydrothermal reaction of 1,10-phenanthroline with CdCl2·2.5H2O in aqueous solution leads to the complex of [Cd(μ-Cl)2(phen)]n (phen=1-10-phenanthroline).The crystal structure has been determined by X-ray analysis.It crystallizes in monoclinic with space group C2/c,a=16.947(3),b=10.529(1)(A),β110.795(3),V=1208.8(3)(A)3,Z=4,Dc=1.997g,cm-3, μ=2.22mm-1,F(000)=704,R=0.0231,Rw=0.626 for 1194 reflections with with I＞2δ(I).In the crystal structure ,the [Cd(phen)]2+ units are bridged by chloride ions to form 1D chain. The 1D chains combine through π…π interactions of phen groups to form 2D infinite molecular zipper. 相似文献
5.
为了改善海藻酸钠固定化酶微球的扩散性与酶活稳定性,以纳米二氧化钛修饰海藻酸为固定化酶载体,Ca2+,Ce3+,Ni2+,Cu2+和Fe3+为杂化凝胶的阳离子交联剂,木瓜蛋白酶为模型酶,制备固定化酶微球.通过UV-Vis光谱检测酶活,考察了5种交联剂对固定化酶的动力学和稳定性的影响,结果表明:当Cu2+为交联剂时,固定化酶具有最高的亲和性、最低的米氏常数(Km=11.0 mg/m L)和最高的稳定性.研究了TiO 2与木瓜蛋白酶的质量比对固定化酶稳定性以及酶蛋白泄漏的影响,结果显示纳米二氧化钛与木瓜蛋白酶的质量比为10∶1时,制备的固定化酶微球性能最好,因为二氧化钛能有效阻止固定化酶的泄漏.通过离子胶凝制备Cu/海藻酸/TiO 2杂化凝胶可获得较好的扩散能力和酶活稳定性. 相似文献
6.
LAN Zi-dong 《重庆大学学报(英文版)》2016,15(1):35-42
A new kind of polycarboxylate superplasticizer with high slump loss resistance was obtained by designing scheduled molecular structure. The number average molecular mass of the polymer was characterized by the gel permeation chromatography measurements. And chemical structure of the polymer was observed by the Fourier transform infrared spectroscopy (FT-IR). The results show that the good workable maintaining of self-compacting concrete could be achieved through direct adjustment of number average molecular mass and different unsaturated monomer in synthetic process. The FT-IR analysis illustrated that the high slump loss resistance of polycarboxylate superplasticizers with ester and carboxyl group and expectations of molecular structure were designed. 相似文献
7.
用经典分子动力学以及量子化学的一种自洽求解数值方法 MNDO(m odified neglect of diatom ic overlap)研究了C6 0 原子团簇电子结构 .同时考虑σ-轨道和π-轨道 ,计算了一个电子能量级、对称性、π-轨道包含率、电子激发能量、凝聚能量、离子化能量以及电子亲和力 .得到的分子轨道比率显示了 σ-轨道和 π-轨道之间的明显分离 ,π-轨道大部分存在于HOMO-和 L U MO-能量级附近 .计算结果与对应的实验数值相当一致 相似文献
8.
A series of high molecular weight PVC (HMW-PVC) resin was synthesized by suspenion process at various temperatures and compounded
to prepare plasticized HMW-PVC. Plasticized HMW-PVC is physically crosslinked by microcrystallites and chain entanglements.
The molecular weight and degree of crystallinity of PVC resin increase with decrease of polymeri-zation temperature. More
dense physical crosslinking networks are formed in plasticized PVC with the decrease of polymerization temperature of PVC
resin. Plasticized HMW-PVC exhibits thermal reversible processability, but the gelation temperature and melt viscosity increase
with increasing physical crosslinking density. Physical crosslinking also has great effects on the mechanical properties of
plasticized HMW-PVC. The compression set and deformation decrease as molecular weight and crystallinity of PVC resin increase,
but the softening temperature and tensile strength increase. The crosslinking network of plasticized HMW-PVC is more similar
to the dissociable network of gels than to the permanent network of crosslinked rubber and is not stable under stretching
at high stress. 相似文献
9.
ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｍｅｃｈａｎｉｃａｌｐｒｏｐｅｒｔｉｅｓｏｆｐｌａｓｔｉｃｉｚｅｄＰＶＣａｒｅｖｅｒｙｓｔｒｏｎｇｅｖｅｎｉｆｔｈｅｍａｔｅｒｉａｌｉｓｕｓｅｄｗｅｌｌａｂｏｖｅｉｔｓｇｌａｓｓｔｒａｎｓｉｔｉｏｎｔｅｍｐｅｒａｔｕｒｅ(Ｔｇ).Ｔｈｅｆｌｏｗａｎｄｖｉｓｃｏｅｌａｓｔｉｃｂｅｈａｖｉｏｒａｒｅｓｉｍｉｌａｒｔｏｔｈａｔｏｆａｌｉｇｈｔｌｙｃｒｏｓｓｌｉｎｋｅｄｒｕｂｂｅｒ.Ｔｈｉｓｈａｓｂｅｅｎｔｈｅｓｕｂｊｅｃｔｏｆｍｕｃｈｄｅｂａｔｅ,ｂｕｔｔｈｅｍｏｓｔｒｅａｓ… 相似文献
10.
黄崇智 《内江师范学院学报》2008,23(8):5-10
将完全k方数的概念由N推广到R^＋,从而得到一个引理,由之推出一系列有关无理数的命题．此外,关于√2^√2,2^√2,α^β为≠0,1的代数数,而β乃不为有理数的代数数）,e＋π,e·π,e^π,π^e,2^e与2^π的无理性的简单证明也分别在此给出． 相似文献
11.
以硫酸亚铁为催化剂,琼脂与双氧水反应制备了氧化琼脂,并对其性能进行了表征。性能测试结果显示,氧化后琼脂的凝胶温度、凝胶再溶温度、凝胶强度、溶胶旋光度、溶胶表观粘度均降低,而保水性增强;氧化琼脂与原料琼脂的凝胶骨架结构均为多孔性网状结构;质构特性参数中硬度、脆性、弹性、咀嚼性随琼脂氧化程度的增加逐渐降低,而内聚性却逐渐增加。 相似文献
12.
采用水溶液法,合成了铁配合物[Fe（C12H8N2）3]（C6H6N2S2O6）.4H2O,该配合物晶体属三斜晶系,P-1空间群,晶胞参数是：a=12.8789（12）,b=13.3808（13）,c=14.859（2）,α=104.558（2）°,β=100.780（2）°,γ=107.5760（10）°,V=2264.8（5）3,Z=2.铁离子周围有6个由1,10-邻菲罗啉提供的氮原子与之配位形成畸变的八面体的配位构型.相邻结构单元中的邻菲罗啉分子存在着弱的π-π堆积作用,没有参与配位的邻苯二胺-3,5-二磺酸根离子与结晶水分子通过氢键将配合物扩展为二维超分子结构. 相似文献
13.
本文研究了概率空间与集值概率空间的关系,指出概率空间与集值概率空间可以相互诱导。证明集合是闭集,得到了K_x的结构表示定理,然后讨论了集值概率测度P_x_p和概率测度P_x的有关性质。 相似文献
14.
合成了一种新颖的配合物[Zn(H2O)(bpp)(Bript)2]n(其中,bpp=1,3-二(4-吡啶)丙烷,H2Bript=5-溴间苯二甲酸),并用X-射线单晶衍射仪测定了其结构.晶体数据表明,该配合物属单斜晶系,空间群P21/c,晶胞参数为:a=7.862(3),b=27.530(10),c=9.664(4),β=96.694(6)°,V=2077.6(13)3,Z=4,Dcalc=1.677 g·cm-3,μ=3.141 mm-1,F(000)=1056,R1=0.1119,wR2=0.2760.在配合物中,Zn原子被5-溴间苯二甲酸离子连接为一维链,这些一维链通过氢键和π…π相互作用连接在一起形成二维超分子化合物. 相似文献
15.
四氟硼酸镍溶液与2-吡嗪甲酸反应生成了一个单核配位化合物[Ni(Pz)2](Pz=2-pyrazinecarboxylatic acid)。配合物结构中的单核单元通过T…π堆积作用相互联系在一起,进而向二维空间伸展,构成了配合物[Ni(Pz)2]的二维超分子结构。对配位化合物[Ni(Pz)2]光致发光性能的研究发现,配合物[Ni(Pz)2]又展示出了一个大概位于433 nm的宽阔的发射峰。其荧光发射机理被归属为配体内部的π-π*电子跃迁。 相似文献
16.
以邻菲罗啉(Phen)和邻氨基苯磺酸为配体,与硝酸镍利用水热合成法合成标题配合物{[Ni(Phen)3]·L·(OH)}(L=邻氨基苯磺酸阴离子)。通过红外光谱和元素分析对标题配合物进行结构表征,X-射线单晶衍射结果表明,标题配合物的分子式为:C42H31O4N7SNi,Mr=788,属单斜晶系,空间群为C2/c,晶胞参数:a=23.119?,b=15.792?,c=25.040?,β=111.2°,V=8523.3?3,Z=8,R1=0.0808,ωR2=0.2447。标题配合物由一个配阳离子[Ni(Phen)3]2+,一个邻氨基苯磺酸阴离子和一个氢氧根离子组成。在配阳离子中,中心Ni(II)与三个phen分子的六个氮原子配位,形成六配位的八面体构型。配阳离子通过静电引力与阴离子结合。化合物分子间通过氢键和Phen环π-π堆积作用形成三维结构。 相似文献
17.
利用水热反应合成了超分子化合物1,2-二（2-苯并咪唑基）乙烷磷酸盐（C16H16N4）（H2PO4）（2H2O）2,利用元素分析、红外光谱、紫外光谱和X-射线单晶衍射对其结构进行了表征.该化合物属于单斜晶系,P21/n空间群,a=0.703 1（5）nm,b=1.774 3（13）nm,c=0.846 9（7）nm,β=106.351（9）°,V=1.013 9（13）nm3,Z=2,Dc=1.619 g/cm-3,F（000）=516,μ=0.281 mm-1,GOF=1.043,R1=0.051 3,wR2=0.166 8.单胞分子间通过氢键及π-π堆积作用相互形成三维网状超分子结构. 相似文献
18.
An efficient reflux extraction of polyethylene wax （PEW） in soil is presented, followed by molecular structure characterization methods to explore its degradation mechanism. To more realistically simulate the actual degradation of PE film powders in soil, low density PE （M=5 000） powders, being used as simulated PEW residue sample, were uniformly mixed with soil and then recovered by reflux extraction with decahydronaphthalen （decalin） at 90 ℃ for 60 min. The average recovery of PEW from fortified soils was 96.5% with the developed reflux extraction procedure. The recovered PEW residue samples were characterized by infrared spectroscopy （IR）, element analysis （EA）, X-ray fluorescence （XFR）, and high-temperature gel permeation chromatography （GPC）. The results from spectra analysis show that there were no significant changes in molecular structures and molecular mass distribution of PEW samples after the reflux extraction, which demonslrate the reliability of this method. These results also indicate that the reflux extraction procedure and analytical methods of characterization could serve as a novel measurement technique to evaluate the degradation of low-density PE powders in soil over time. 相似文献
19.
Hong-bo PENG Di ZHANG Hao LI Chi WANG Bo PAN 《浙江大学学报(A卷英文版)》2014,15(8):606-617
研究目的：碳纳米颗粒由于其独特的优良性能被广泛应用,从而不可避免地进入环境。进入环境的碳纳米颗粒与有机污染物有很强的相互作用,并且碳纳米颗粒对有机污染物的吸附可能会影响污染物的环境风险和迁移。因此,本研究总结了目前有机污染物在碳纳米颗粒上吸附的研究进展,为有机污染物及碳纳米颗粒的环境行为研究及风险评价提供重要信息。重要结论：有机污染物和碳纳米颗粒的主要相互作用有憎水性、静电、氢键和π-π作用,这些作用及它们的强度受碳纳米颗粒的表面性质、形态及有机污染物的分子大小、结构和官能团等影响。不同的吸附机理可能同时控制有机物在碳纳米颗粒上的吸附过程,而且在不同的环境条件下吸附控制机理不同。区分吸附控制机理和影响因素的研究对预测有机污染物和碳纳米颗粒的环境行为和风险非常重要。 相似文献
20.
研究了含硫芳香族(苯磺酰基环烷烃甲酸酯)化合物对发光菌的毒性与其拓扑指数之间的定量关系,相关性良好,结果表明计算值与实验值较吻合. 相似文献