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采用线性吸收谱和二次谐波产生技术研究了温度对具有中心对称结构的稀土夹心双萘酞菁化合物LB膜光学特性及其LB膜结构的影响。研究发现,加热可以使其LB膜的结构及分子间的相互作用发生变化,并形成J聚集体,从而使得吸收峰发生红移。稀土夹心双萘酞菁化合物约在40 ℃时其二次谐波信号有一个极小值,约在65 ℃时该化合物发生相变,使得二次谐波信号产生极大值,二次谐波信号最小时温度可高达180 ℃,说明该化合物的化学结构较为稳定。 相似文献
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采用紫外可见吸收和二次谐波产生技术研究了“推-拉”型偶氮苯分子Langmuir-Blodgett(LB)膜的光谱和二阶非线性光学特性.4-硝基-4′-氨基偶氮苯(NAA)分子能制成很好的LB多层膜,在稀溶液中以单体的反式异构体形式存在,在膜中主要以J-聚集体的形式存在,LB膜的紫外可见吸收谱的吸收峰较之溶液的发生了52 nm的红移.NAALB膜的二阶非线性极化率χ(2)为19.59×10-8 esu,一阶超极化率β值较大,约为1.974×10-29 esu.其光学二阶非线性起源于电偶极子机制. 相似文献
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LB膜的各向异性与二次谐波超平方增长 总被引:2,自引:2,他引:0
用偏振紫外-可见吸收及旋转样品二次谐波方法研究了半花菁/花生酸Y型交替LB多层膜中由垂直浸渍过程诱导和层间相互作用增强的分子在基板平面内的定向排列,提出并证实了随层数增长的平面内附加偶极矩导致光学二次谐波强度随LB膜厚度的超平方增长关系。 相似文献
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一种可溶喹吖啶酮衍生物LB膜的光谱特性 总被引:1,自引:0,他引:1
采用表面压-分子面积(π~A)等温曲线、紫外-可见吸收谱和荧光光谱的方法研究了一种喹吖啶酮衍生物材料LB膜的制备及其光谱特性。实验表明,这种喹吖啶酮衍生物能够在水面上形成稳定的单分子膜,它与花生酸(AA)混合后不仅可以形成很好的单分子膜,而且可以较好的转移到固体基片上制备成LB膜多层膜。这种喹吖啶酮衍生物LB膜的紫外-可见吸收谱的吸收峰位较稀溶液发生了红移,这是由极性溶剂分子与其相互作用的结果。其溶液有很强的荧光效应,但LB膜没有荧光现象,原因是在LB膜中QAC16的浓度过高发生“自我猝息”而失光。它在溶液和LB膜中都是以单体的形式存在。 相似文献
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对一种新型的,具有双脂链的盘状非活性分子氮冠(醚)(NC)LB膜进行了表征。小角X射线衍射(SAXD)结果表明:纯NC分子可以形成非常好的LB膜有序结构。将它与活性分子半花菁(DAEP)制备成Y型交替多层膜,由于半花菁分子的单脂链(长尾)可以镶嵌在NC分子的双脂链之间,改善了多层膜的结构有序性及稳定性,从而得到二次谐波强度随层数的变化在1 ̄116双层范围内显示出较理想的平方关系。通过二次谐波的测量 相似文献
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用吸收光谱对染料的Langmuir-Blodgett(LB)膜的聚集体在不同条件下进行了研究.典型的染料1-methyl-1’-octadecy1-2,2’-cyaninperchlorate(MOC)LB膜聚集体的吸收峰(J带)在580nm附近,吸收为0.09.刚制备好的样品随时间而改变其吸收特性,表明聚集体的结构在2hr后才趋于稳定;测定了不同样品J带的参数;吸收峰值波长位置和峰的半宽度,以及这些参数随温度的变化.吸收随温度变化的可逆性是LB膜聚集体用作光记录介质的一个物理基础.温度超过100℃时,样品吸收的不可逆变化反映相变发生. 相似文献
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两种烷基取代喹吖啶酮衍生物LB膜的荧光特性 总被引:1,自引:0,他引:1
制备了两种烷基取代喹吖啶酮衍生物C6DHQA和C16DMQA的X型Langmuir-Blodgett(LB)膜,采用紫外-可见吸收、稳态荧光和时间分辨荧光的方法研究其溶液及LB的光学特性。研究结果表明,C16DMQA比C6DHQA的吸收谱整体红移,说明烷基链加长减小了分子的能级间隔;两者LB膜的吸收谱较溶液整体红移,说明在LB膜中形成了"J-聚集体"。两种材料的溶液及LB膜都有较强的荧光发射,溶液的荧光谱与吸收谱有很好的镜像对称关系,形成LB膜后,镜像对称关系被打破,两者第三个荧光峰相对强度差别很大。C6DHQA溶液中的荧光寿命为21ns左右,C16DMQA溶液中的荧光寿命为22ns左右,形成LB膜后,荧光寿命明显较少,两者第三个荧光峰对应的荧光寿命差别较大。其原因应归于C16DMQA分子在基板上的排列更密,分子间的相互作用力强,从而对能级结构的影响更大。 相似文献
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B. I. Stepanov Institute of Physics, Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072, Belarus. Translated
from Zhurnal Prikladnoi Spektroskopii, Vol. 62, No. 2, pp. 200–205, March–April, 1995. 相似文献
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A. I. Akimov A. N. Baranov L. V. Levshin A. M. Saletskii 《Journal of Applied Spectroscopy》1996,63(2):188-193
M. V. Lomonosov Moscow State University, Vorob'yovy Gory, Moscow, 119899, Russia. Translated from Zhurnal Prikladnoi Spektroskopii,
Vol. 63, No. 2, pp. 236–241, March–April, 1996. 相似文献
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Stable-plasma generators, spectroscopic measuring equipment, and methods for determining the optical properties of an extremely
heated medium with a given composition have been developed. The spectral coefficients of absorption and emission of heated
air, carbon dioxide, and argon were studied. A comparison with the data of other theoretical and experimental investigations
has been performed.
Deceased.
Institute of Molecular and Atomic Physics of the Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072, Belarus.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 6, pp. 818–826, November–December, 1997. 相似文献
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A. P. Losev I. N. Nichiporovich S. M. Bachilo G. D. Egorova D. I. Volkovich K. N. Solov'yo 《Journal of Applied Spectroscopy》1995,62(2):311-320
Institute of Molecular and Atomic Physics, Academy of Sciences of Belarus, Minsk, 220072, 70, F. Skorina Ave., Belarus. Translated
from Zhurnal Prikladnoi Spektroskopii, Vol. 62, No. 2, pp. 152–163, March–April, 1995. 相似文献
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Ehrlich H Koutsoukos PG Demadis KD Pokrovsky OS 《Micron (Oxford, England : 1993)》2008,39(8):1062-1091
In contrast to biomineralization phenomena, that are among the most widely studied topics in modern material and earth science and biomedicine, much less is systematized on modern view of demineralization. Biomineralized structures and tissues are composites, containing a biologically produced organic matrix and nano- or microscale amorphous or crystalline minerals. Demineralization is the process of removing the inorganic part, or the biominerals, that takes place in nature via either physiological or pathological pathways in organisms. In vitro demineralization processes, used to obtain mechanistic information, consist in the isolation of the mineral phase of the composite biomaterials from the organic matrix. Physiological and pathological demineralization include, for example, bone resorption mediated by osteoclasts. Bioerosion, a more general term for the process of deterioration of the composite biomaterials represents chemical deterioration of the organic and mineral phase followed by biological attack of the composite by microorganisms and enzymes. Bioerosional organisms are represented by endolithic cyanobacteria, fungi, algae, plants, sponges, phoronids and polychaetes, mollusks, fish and echinoids.In the history of demineralization studies, the driving force was based on problems of human health, mostly dental caries. In this paper we summarize and integrate a number of events, discoveries, milestone papers and books on different aspect of demineralization during the last 400 years. Overall, demineralization is a rapidly growing and challenging aspect of various scientific disciplines such as astrobiology, paleoclimatology, geomedicine, archaeology, geobiology, dentistry, histology, biotechnology, and others to mention just a few. 相似文献
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Institute of Molecular and Atomic Physics Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072, Belarus. Translated
from Zhurnal Prikladnoi Spektroskopii, Vol. 62, No. 2, pp. 128–136, March–April, 1995. 相似文献
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一次性消解-原子吸收光谱法、原子荧光光谱法检测水产品中铅、镉、铜、锌和砷 总被引:3,自引:0,他引:3
采用湿法消解一次性处理水产品,塞曼石墨炉原子吸收光谱法测定铅、镉、铜,火焰原子吸收光谱法测定锌、氢化物发生-原子荧光光谱法测定砷.该方法简便、快速,通过优化前处理和上机条件,在最优条件下进行测试,铅、镉、铜、锌、砷的检出限分别为0.012、0.001、0.008、0.089、0.009mg/kg,回收率范围为87.6%-110%,相对标准偏差为3.9%-6.8%.通过测定有证标准物质,证明该方法具有很好的准确度. 相似文献
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M. M. Mirinoyatov 《Journal of Applied Spectroscopy》1996,63(6):830-832
Tashkent State University, Department of Physics, TashSU, Vuzgorodok, Tashkent, 700095 Uzbekistan. Translated from Zhurnal
Prikladnoi Spektroskopii, Vol. 63, No. 6, pp. 974–976, November–December, 1996. 相似文献
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A. I. Trokhimets 《Journal of Applied Spectroscopy》1995,62(1):88-90
Institute of Physicoorganic Chemistry, Academy of Sciences of Belarus, 220603, Minsk, Ul. Surganova, 13, Belarus. Translated
from Zhurnal Prikladnoi Spektroskopii, Vol. 62, No. 1, pp. 104–107, January–February, 1995. 相似文献