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41.
Jing Yu Jingwei Han Chuanzhong Li 《Mathematical Methods in the Applied Sciences》2020,43(6):3076-3085
For the orthosymplectic Lie superalgebra , we choose a set of basis matrices. A linear combination of those basis matrices presents a spatial spectral matrix. The compatible condition of the spatial part and the corresponding temporal parts of the spectral problem leads to a generalized super AKNS (GSAKNS) hierarchy. By making use of the supertrace identity, the obtained GSAKNS hierarchy can be written as the super bi-Hamiltonian structures. 相似文献
42.
Synthesis of polyphosphodiesters by ring‐opening polymerization of cyclic phosphates bearing allyl phosphoester protecting groups 下载免费PDF全文
Benoït Clément Daniel G. Molin Christine Jérôme Philippe Lecomte 《Journal of polymer science. Part A, Polymer chemistry》2015,53(22):2642-2648
The allyl phosphoester group is shown to be a protecting group for the synthesis of anionic polyphosphodiesters. Our strategy relies on the synthesis of a cyclic phosphate monomer bearing a pendant allyl phosphoester group, its easy purification by fractional distillation, its organocatalyzed ring‐opening polymerization by 1,8‐diazobicyclo[5.4.0]undec‐7‐ene (DBU) and 1‐[3,5‐bis(trifluoromethyl)phenyl]‐3‐cyclohexyl‐thiourea (TU). Finally, the deprotection of the allyl phosphoester group is carried out by reaction with sodium benzenethiolate in the absence of any detectable degradation. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 2642–2648 相似文献
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直接吸收光谱(DAS)可直接测量分子吸收率函数,并通过拟合吸收率函数确定待测气体参数.波长调制-直接吸收光谱(WM-DAS)在DAS基础上,结合了波长调制光谱(WMS)中谐波分析思想,利用傅里叶变换复现吸收率函数,可有效提高吸收率函数的测量精度.本文利用WM-DAS方法结合长光程气体吸收池,在室温低压条件下,对CO分子1567 nm处R5-R11近红外弱吸收谱线吸收率函数进行了精确复现,其拟合残差标准差低至3×10^-5,随后根据测得的吸收率函数对谱线的碰撞展宽、Dicke收敛以及速度依赖的碰撞展宽系数等光谱参数进行了高精度标定,并将其与高灵敏度的连续波腔衰荡光谱(CW-CRDS)测量结果进行了比较,实验结果表明该方法与CW-CRDS测量结果具有高度一致性,更具有系统简单、测量速度快、对环境要求低等优点. 相似文献
44.
Reversibly light‐responsive biodegradable poly(carbonate) micelles constructed via CuAAC reaction 下载免费PDF全文
Ding Hu Hua Peng Yile Niu Yefei Li Yingchun Xia Ling Li Jingwen He Xiangyu Liu Xinnian Xia Yanbing Lu Weijian Xu 《Journal of polymer science. Part A, Polymer chemistry》2015,53(6):750-760
Light‐responsive poly(carbonate)s PEG113‐b‐PMPCn‐SP were synthesized via copper catalyzed azide‐alkyne cycloaddition reaction between azide‐modified spiropyran (SP‐N3) and amphiphilic copolymer PEG113‐b‐PMPCn. PEG113‐b‐PMPC25‐SP can self‐assemble to biocompatible micelles with an average diameter of ~96 nm and a critical aggregation concentration of 0.0148 mg mL?1. Under 365 nm UV light irradiation, the characteristic absorption intensity of merocyanine (MC) progressively increased and most of the micellar aggregations were disrupted within 10 min, suggesting the completion of the transformation of hydrophobic SP to hydrophilic MC. Subsequent exposuring the micelles to 620 nm visible light, spherical micelles aggregated again. The light‐controlled release and re‐encapsulation behaviors of coumarin 102‐loaded micelles were further investigated by fluorescence spectroscopy. This study provides a convenient way to construct smart poly(carbonate)s nanocarriers for controlled release and re‐encapsulation of hydrophobic drugs. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 750–760 相似文献
45.
Jatropa curcas Linn. (JcL) capsule husk was not recommended as biogas feedstocks. However for biorefinery purpose, several technologies have been conducting to solve this problem. This research reported quantity and quality comparison of Dry Husk Jcl (DH-JcL) in one phase system of batch digester compare with semi continuous digester. HDPE drum of 80 L working volume used as digester with 40 days hydraulic retention time. Feeding of DH-Jcl and solvent water was mixed on concentration of 1: 8. Research conclusion showed that semi continuous digester was better than batch digester. Biogas quality showed that methane content can reach 66.61% to 83.15% and biogas quantity in semi continuous digester can reach 0.016 m3 · kg–1 DH JcL. The result was not in optimize condition yet because ratio number of volatile fatty acids/ alkalinity showed 0.5, it was indicated unstable anaerobic degradation process of DH-JcL. 相似文献
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Wenbin Guo Dr. Nathalie Daro Dr. Sébastien Pillet Dr. Mathieu Marchivie Dr. El-Eulmi Bendeif Dr. Elodie Tailleur Dr. Kittipong Chainok Dominique Denux Dr. Guillaume Chastanet Prof. Philippe Guionneau 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(57):12927-12930
The current craze for research around the spin crossover phenomenon can be justified to some extent by the mechanical properties due to the decrease of volume associated with the transition of the metal ion from the HS state to the LS state. As demonstrated here, the molecular complex [Fe(PM-pBrA)2(NCS)2] exhibits, on the contrary, an increase of the unit-cell volume from HS to LS. This counter-intuitive and unprecedented behavior that concerns both the thermal and the photoexcited spin conversions is revealed by a combination of single-crystal and powder X-ray diffraction complemented by magnetic measurements. Interestingly, this abnormal volume change appears concomitant with the wide rotation of a phenyl ring which induces a drastic modification, though reversible, of the structural packing within the crystal. In addition, the light-induced HS state obtained through the Light-Induced Excited Spin-State Trapping shows a remarkably high relaxation temperature, namely T(LIESST), of 109 K, one of the highest so far reported. The above set of quite unusual characteristics opens up new fields of possibilities within the development of spin crossover materials. 相似文献
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