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391.
对严重重叠的光谱干扰校正,采用较小间隔的光谱扫描测量,并用间隔扫描点的数据计算,可减小计算结果的误差,提高结果的准确性。本方法用于校正Nd359.259nm对Sm359.260nm和V328.939nm对Yb328.937nm谱线重叠干扰,得到了满意的结果。  相似文献   
392.
通过金相光学显微镜、图像分析仪和扫描电镜及能谱仪对现场耐候钢板坯和洁净度较好的两组试验耐候钢板坯进行分析观察,采用非水电解分离夹杂 ICP方法分析钢中固溶稀土含量.从而从稀土变质夹杂的角度研究得出在不同的氧、硫含量下稀土的最佳最经济加入量及稀土的最佳含量对非金属夹杂物的影响.  相似文献   
393.
N (反式 4 异丙基环己基 1 甲酰基 ) D 苯丙氨酸 ,药品名那格列奈 ,作为治疗二型糖尿病的药物1 999年在日本上市 ,药效与其晶体存在的型态密切相关。B型晶不稳定 ,H型晶对研磨的稳定性较高 ,比B型晶更适合于制药[1 ] 。此外 ,我们发现B型或H型晶在一定条件下可转化为熔点较高的第三种样品———VH型晶。测定了三种那格列奈样品的熔点 ,用示差扫描量热 (DSC)、热重差热 (TGA DTA )、红外 (IR)及X 射线粉末衍射 (XRD)等对它们进行了表征。那格列奈的分子结构如下图所示 :1 实验部分1 1 制备B晶熔点 1 2 8~ 1 3…  相似文献   
394.
Reactions of 3-methyl-1,8-dihydrocycloheptapyrazol-8-one ( 2 ) with arylamines in the presence of formaldehyde gave 1-(N-arylaminomethyl)-3-methyl-1,8-dihydrocycloheptapyrazol-8-ones 5a-l in good yields. 1,3,5-Tris(phenyl- and 4-methoxyphenyl)hexahydro-1,3,5-triazines or bis(3-nitroanilino)methane, which were condensation products of arylamines and formaldehyde, also reacted with compound 2 to afford 5a,c,j , respectively.  相似文献   
395.
The urea decomposition property at high temperature has been used to control the pH value in the synthesis of layer compounds. The hydrotalcites of Mg-Al and Ni-Al with high crystallinity were synthesized by using this property.  相似文献   
396.
Advanced nanotechnology has been emerging rapidly in terms of novel hybrid nanomaterials that have found various applications in day-to-day life for the betterment of the public. Specifically, gold, iron, silica, hydroxy apatite, and layered double hydroxide based nanohybrids have shown tremendous progress in biomedical applications, including bio-imaging, therapeutic delivery and photothermal/dynamic therapy. Moreover, recent progress in up-conversion nanohybrid materials is also notable because they have excellent NIR imaging capability along with therapeutic benefits which would be useful for treating deep-rooted tumor tissues. Our present review highlights recent developments in inorganic–inorganic nanohybrids, and their applications in bio-imaging, drug delivery, and photo-therapy. In addition, their future scope is also discussed in detail.

The present review will be detailing about trending inorganic–inorganic nanohybrids that have been used for various biomedical applications including drug-delivery, bio-imaging and photo therapy.  相似文献   
397.
A gel polymer electrolyte (GPE) was prepared by in-situ thermal polymerization of 1,3-butanediol diacrylate (BDDA) in a EC/EMC/DMC electrolyte solution at 100 °C. The GPE with 15 wt.% polymer content appears as apparently dry polymer with sufficient mechanical strength and shows a high ionic conductivity of 3.2×10–3 S cm–1 at 20 °C. The MCMB–LiCoO2 type polymer Li-ion batteries (PLIB) prepared using this in-situ internal polymerization method exhibit a very high initial charge–discharge efficiency of 92.1%, and can deliver 94.4% of its nominal capacity at 1.0 C rate and 70.7% of its room temperature capacity at –20 °C. Also, the PLIB cells show very good cycling ability with >85% capacity retention after 300 cycles. The excellent charge–discharge properties of the PLIB cells are attributed to the integrated structure in which the polymer matrix spreads over entire region of the cell acting as a strong binder and electrolyte carrier to produce a stabilized electrode–electrolyte interface. In addition, the fabricating process of the polymer cell is quite simple and convenient for practical applications.  相似文献   
398.
3-Acetyltropolone ( 1a ) reacted with 2-aminobenzaldehydes in the presence of sodium ethoxide to afford 3-(2-quinolyl)tropolone ( 3aa ) in 96% yield. Methyl- and isopropyl-substituted tropolones 1b,c also gave six 3-(2-quinolyl)tropolones in excellent yields. The compound 3aa was allowed to stand in 40% aqueous methylamine solution to give 7-methylamino-2-(2-quinolyl)tropone ( 4 ).  相似文献   
399.
The micelle formation of a series of amphiphilic block copolymers in aqueous and NaCl solutions was studied by a fluorescent probe technique using pyrene as a "model drug". These copolymers were synthesized from poly (ethylene glycol) (PEG) and l-lactide by a new calcium ammoniate catalyst. They had fixed PEG block lengths (44, 104 or 113 ethylene oxide units) and various poly(l-lactide) (PLLA) block lengths (15–280 lactide units). The critical micelle concentration (cmc) was found to decrease with increasing PLLA content. The distinct dissimilarity of the cmc values of diblock and triblock copolymers based on the same block length of PEG provided evidence for the different configurations of their micelles. It was also observed that the introduction of NaCl salt significantly contributed to a decrease in the cmcs of the copolymers with short PEG and PLLA blocks, while it had less influence on the cmcs of copolymers with long PEG or PLLA blocks. The dependence of partition coefficients ranging from 0.2×105 to 1.9×105 on the PLLA content in the copolymer and on the micelle configuration was also discussed. The contribution of NaCl salt to increasing the partition of pyrene into a micellar phase was observed.  相似文献   
400.
Octupolar oligomers containing 2-12 molecules of 1,3,5-tricyano-2,4,6-tris(styryl)benzene derivatives have been synthesized and their nonlinear optical and two-photon absorption (TPA) properties were determined. The beta(0) values are in the range of (85-1219) x 10(-30) esu and increase monotonically with the increasing number of the octupolar units within the molecule. The two-photon-induced fluorescence excitation spectra are quite similar to the single-photon absorption spectra except that the wavelength is doubled, indicating that the one- and two-photon allowed excited states are the same. The peak TPA cross-section values (delta(max)) measured with nanosecond pulses by the two-photon-induced fluorescence method are in the range (3010-62, 930) x 10(-50) cm(4)s photon(-1). The delta(max) increases as the number of the octupolar units in the molecules increases. A linear relationship is observed between delta(max) and beta, and this delta-beta relationship serves as a useful design strategy for the synthesis of novel octupolar oligomers and polymers with large TPA and beta.  相似文献   
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