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1.
食品的杀菌与储存是食品加工工艺中必须的两个环节。本文利用第二定律的[火用]分析法对满足食品加工特定水温参数需求的冷热联供CO2热泵与传统锅炉冷水机组进行火用分析比较,分析结果表明冷热联供CO2热泵的[火用]效率高于传统冷水机组[火用]效率相当。最后阐述了冷热联供CO2热泵在食品行业的应用前景。  相似文献   

2.
为进一步认识羟基[60]富勒烯吡咯烷衍生物的空间结构,借助密度泛函考察了羟基取代位置和取代基数量对羟基[60]富勒烯吡咯烷衍生物空间结构的影响。结果显示,5种羟基[60]富勒烯吡咯烷衍生物的LUMO均集中在[60]富勒烯上,羟基出现在邻位时其衍生物的LUMO和HOMO能量差ΔE最小,而羟基在间位时其ΔE最大。吡咯烷键长和键角并不随羟基数量的增加而呈规律性的变化,但羟基取代基位置对吡咯烷键长和键角的影响由大到小的顺序是:对位、间位、邻位。  相似文献   

3.
在微波辐射下,1-甲基咪唑分别与有机卤盐(1-溴丙烷、1-溴丁烷、1-溴己烷)在80℃回流加热10min,可制得咪唑类离子液体的中间体溴代1-丁基-3-甲基咪唑([BMIm]Br)、溴代1-丙基-3-甲基咪唑([PMIm]Br)、溴代1-己基-3-甲基咪唑([C6MIm]Br),进一步与HPF6在室温搅拌反应4h,制得憎水性的咪唑类离子液体[BMIm]PF6,[PMIm]PF6和[C6MIm]PF6。对这3种离子液体及其在不同有机溶剂如丙酮、甲醇、乙酸乙酯中的电导率进行测定,发现离子液体的电导率受咪唑上取代基种类、溶剂种类、浓度和温度的影响,取代基的链越长,体积越大,离子液体的电导率越小。并且随温度升高和浓度的增大,离子液体的电导率也增大。  相似文献   

4.
以七甲基三硅氧烷(MDHM)、乙烯基三甲氧基硅烷(VTMS)为原料,氯铂酸的异丙醇溶液为催化剂,采用硅氢加成反应,在氮气保护下合成1,1,1,3,5,5,5-七甲基-3-[2-(三甲氧基硅烷基)乙基]三硅氧烷(β-HTEOs),并用气相色谱-色谱连用(GC-MS)、核磁共振谱(1H-NMR、29 Si-NMR)、傅里叶红外变化光谱(FT-IR)对合成产物进行表征;通过探讨反应温度、反应时间、原料配比以及催化剂浓度对硅氢加成反应的影响,得到β-HTEOs合成的最优化条件,采用视频接触角仪测定其在玻璃基材上润湿铺展情况,表明β-HTEOs在玻璃基材上完全铺展,具有较低的表面张力.  相似文献   

5.
液晶光控取向材料是近年来国际上的一个研究热点,其中光交联型材料因其稳定性强、取向效果好等优点被广泛研究。文中综述了肉桂酸酯类、香豆素类、苯乙烯基吡啶类、苯乙烯基苯并吡咯酮类、二苯基乙炔类光交联型液晶光控取向材料的研究进展,并对其光化学反应机理进行了分析。  相似文献   

6.
AgNO3乙腈溶液注入热的苯甲醛,一步法合成了不同形貌和粒径的纳米银颗粒;硝酸银的乙腈溶液注入热的C60-二甲苯和苯甲醛混合液中,一步原位合成了富勒烯[60]-纳米银复合物。用X射线衍射(XRD)、透射电镜(TEM)、元素分析、傅里叶变换红外光谱(FT-IR)分析证实了富勒烯[60]-纳米银复合物的形成。对纳米银晶粒形成过程和富勒烯[60]-纳米银复合物的形成进行了初步的解释。  相似文献   

7.
金红石TiO2基质中[MoO4]2-基团的上转换发光   总被引:1,自引:0,他引:1  
在978nm激光二极管的激发下,Mo掺杂的TiO2材料表现出很强的宽带上转换发光,该发光来源于[MoO4]^2-基团的激发态3T1,3T2能级到基态1Al能级的电子跃迁.X射线衍射表明样品为金红石单一相,红外吸收光谱证实了[MoO4]2-的存在.由光电子能谱推测体系中还含有低价态的Mo离子,它们提供了上转换得以进行的中间态.高温下的氧化还原处理会改变低价Mo的数量,从而严重影响样品的发光行为。  相似文献   

8.
利用1,3-偶极环加成反应,合成分离得到了一种C60吡咯烷衍生物:N-基-2-(3-羟基苯基)[60]富勒烯吡咯烷,通过单因素方法,探讨了反应条件对产物产率的影响,并得到了最佳工艺条件:反应物摩尔比(C60:3-羟基苯甲醛:N-甲基甘氨酸)为1:2:4,反应温度90℃,反应时间2h,产物的产率可达82%(以消耗的C60计).同时用Uv-Vis、FT-IR、1H-NMR、MS等测试手段表征了产物的结构.  相似文献   

9.
在普通杯芳烃中引入硫原子可以改善了普通杯芳烃的配合性能。通过对叔丁基硫杂杯[4]芳烃与溴乙酸乙酯反应生成杯芳烃酯类衍生物2,继续在水合肼中肼解,得到硫杂杯[4]芳烃酰肼衍生物3,酰肼衍生物3与5,5-亚甲基二水杨酰基二水杨酰氯发生缩合反应,合成了具有对称桥连结构的硫杂杯[4]芳烃桥联氮杂衍生物5。所合成的新化合物的结构经1H NMR、元素分析、ESI-MS等证实。同时探讨了新型硫杂杯[4]芳烃衍生物5与系列-α氨基酸的配合性能。  相似文献   

10.
选择跨临界CO2-[bmim]PF6作为新型的吸收式制冷工质对,考察了CO2在离子液体[bmim]PF6中的溶解度和CO2-[bmim]PF6工质体系的热物性.计算了在给定工况下循环的制冷特性并对结果进行了分析与讨论.  相似文献   

11.
The paper reports on the investigation of reactivity of various imines prepared from esters of alanine, phenylalanine and tyrosine, and various aromatic aldehydes in reactions with [60]fullerene. Almost all imines studied were found not to undergo [2+3]cycloaddition reactions with C60 under continuous reflux in 1,2-dichlorobenzene because of steric hindrances of the substrates. However, imines of pyridine-2-carboxaldehyde readily reacted with C60 to form corresponding pyrrolidinofullerenes with moderate yields. The promoting effect of 2-pyridyl group in the [2+3]cycloaddition reactions was observed as a result of the formation of intramolecular hydrogen bonds in azomethine ylides formed.  相似文献   

12.
Various types of cycloaddition such as [2+1], [2+3], and Diels-Alder reactions have been investigated for the purpose of exohedral functionalization of [60]fullerene and also in few cases of [70]fullerene. Thermal and photochemical activation have been used and lead to a variety of new fullerene derivatives which may be further functionalizable. In addition, a new approach to aza-heterofullerenes has been developed starting from an exohedrally activated fullerene.  相似文献   

13.
Novel supramolecular nanocapsules consisting of [60]fullerene and the macrocycle cucurbit[7]uril via self-assembly are reported. The nanocapsules, which were synthesized in a two-phase reaction at room temperature, were obtained in good yields. The stoichiometry of the product was found to be 1:2.  相似文献   

14.
Abstract

Various types of cycloaddition such as [2+1], [2+3], and Diels-Alder reactions have been investigated for the purpose of exohedral functionalization of [60]fullerene and also in few cases of [70]fullerene. Thermal and photochemical activation have been used and lead to a variety of new fullerene derivatives which may be further functionalizable. In addition, a new approach to aza-heterofullerenes has been developed starting from an exohedrally activated fullerene.  相似文献   

15.
We present a new use of fullerene C60 as a template for the synthesis of cyclic resorcinarenes, The cyclocondensation of 2-methyl-resorcinol with benzaldehyde and hexanal in THF, catalyzed by AlCl3, in the presence of 1%, 5%, and 10% fullerene C60, produces calix[4], [5], and [6] resorcinarenes, with the pentamer and hexamer as the major products. The resorcinarenes were characterized by 1H, 13C NMR, FTIR, FAB+ mass spectrometry, and elemental analysis.  相似文献   

16.
The solid-state mechanochemical reaction of fullerene C60 by the use of a high-speed vibration milling technique has been applied to the nucleophilic addition of an organozinc reagent to C60, [4+2] cycloaddition of C60 with condensed aromatic hydrocarbons, 1,3-dipolar addition of C60 with organic azides, and dimerization of C60.  相似文献   

17.
Abstract

The solid-state mechanochemical reaction of fullerene C60 by the use of a high-speed vibration milling technique has been applied to the nucleophilic addition of an organozinc reagent to C60, [4+2] cycloaddition of C60 with condensed aromatic hydrocarbons, 1,3-dipolar addition of C60 with organic azides, and dimerization of C60.  相似文献   

18.
Abstract

A lysozyme–[60]fullerene adduct was synthesized and isolated for the first time. This adduct was water‐soluble and showed strong interaction between lysozyme and [60]fullerene and was characterized by UV‐VIS and fluorescence energy transfer technique. Keeping possible biomedical applications of [60]fullerene in view, the protein–[60]fullerene interactions were studied taking lysozyme as a model protein.  相似文献   

19.
A new supramolecular system of functionalized [60]fullerene bearing one 2,6-diaminopyridine moiety with a barbituric acid derivative was constructed through six-point hydrogen-bonding interaction. The self-assembly systems were studied by 1H NMR, UV-Vis spectra, and a SEM image.  相似文献   

20.
Abstract

We present a new use of fullerene C60 as a template for the synthesis of cyclic resorcinarenes, The cyclocondensation of 2‐methyl‐resorcinol with benzaldehyde and hexanal in THF, catalyzed by AlCl3, in the presence of 1%, 5%, and 10% fullerene C60, produces calix[4], [5], and [6] resorcinarenes, with the pentamer and hexamer as the major products. The resorcinarenes were characterized by 1H, 13C NMR, FTIR, FAB+ mass spectrometry, and elemental analysis.  相似文献   

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