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21.
根据体上矩阵研究的新近进展,本文给出了任意体上的矩阵力方程的解判别定理及其通解的显式表示,并给出了(1)的一种有实用价值的简便解法。  相似文献   
22.
关于p-除环上分块矩阵秩的一些恒等式   总被引:1,自引:1,他引:0  
本文给出了p-除环上分块矩阵秩的一些恒等式,从而推广了文[1]的结果.  相似文献   
23.
MetapositiveSemidefiniteSolutionstotheMatrixEquationAXB=CoveraStrongp-DivisionRingWangQingwen(王卿文)(DepartmentofMathematics,Ch...  相似文献   
24.
TheMetapositiveDefiniteSelf-ConjugateSolutionoftheMatrixEquationAXB=Cover a Skew FieldWangQingwen(王卿文)(DepartmentofMath.,Chan...  相似文献   
25.
On a Matrix Equation AX+XB=C over a Skew Field   总被引:6,自引:2,他引:4  
In this paper we study a matrix equation AX BX=C (Ⅰ)over an arbitrary skew field,and give a consistency criterion of (Ⅰ) and an explicit expression of general solutions of (Ⅰ).A convenient,simple and practical method of solving (Ⅰ) is also given.As a particular case,we also give a simple method of finding a system of fundamental solutions of a homogeneous system of right linear equations over a skew field.  相似文献   
26.

In this research, the n-butyl palmitate was synthesized using the esterification reaction of the PA with n-butanol. The 1H nuclear magnetic resonance and Fourier transform infrared illustrated that the hydroxyl group and carboxyl group disappeared, and the ester bond appeared after the reaction, explaining that n-butyl palmitate was successfully fabricated. The differential scanning calorimetry indicated that the phase-transition temperature and latent heat are 12.6 °C and 127.1 J g?1, which was suited to use in low-temperature fields such as food, pharmaceutical, and biomedical. The thermogravimetric analysis suggested that it had great thermal stability during the phase change process. In addition, the thermal conductivity of the n-butyl palmitate was slightly higher than other fatty acid ester, and the 500 thermal cycles test results indicated that it had excellent thermal reliability. Therefore, the n-butyl palmitate is deduced to share great thermal energy storage ability in terms of latent heat thermal energy system applications.

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27.
Laportea bulbifera, named Hong He Ma in Chinese, is a Chinese herbal medicine commonly used by the Miao nationality of China. In this study, 43 batches of L. bulbifera were collected from different origins in China. Ethanol, ethyl acetate and petroleum ether were used to prepare different extracts of the plant. UHPLC technique was used to establish the fingerprints, whereas DPPH assay and RAW264.7 inflammatory cell models were used to evaluate the antioxidant and anti-inflammatory activities, respectively. Moreover, the spectrum–effect relationship between relative peak area of common peaks and efficacy value was set up by multivariate statistical analysis. Furthermore, 10 batches were selected randomly for validation of those models. The results showed that ethyl acetate and petroleum ether extracts possess excellent antioxidant and anti-inflammatory activities, respectively. Peaks A6 and A7 demonstrated the greatest antioxidant activity, while peak A17 showed the strongest anti-inflammatory activity. After a verified experiment, the result was obtained and illustrated that the spectrum–effect relationship which we established could reliably infer antioxidant and anti-inflammatory compounds of the Chinese herbal medicine.  相似文献   
28.
Lysozymes are known as ubiquitously distributed immune effectors with hydrolytic activity against peptidoglycan, the major bacterial cell wall polymer, to trigger cell lysis. In the present study, the full-length cDNA sequence of a novel sea urchin Strongylocentrotus purpuratus invertebrate-type lysozyme (sp-iLys) was synthesized according to the codon usage bias of Pichia pastoris and was cloned into a constitutive expression plasmid pPIC9K. The resulting plasmid, pPIC9K-sp-iLys, was integrated into the genome of P. pastoris strain GS115. The bioactive recombinant sp-iLys was successfully secreted into the culture broth by positive transformants. The highest lytic activity of 960 U/mL of culture supernatant was reached in fed-batch fermentation. Using chitin affinity chromatography and gel-filtration chromatography, recombinant sp-iLys was produced with a yield of 94.5 mg/L and purity of >?99%. Recombinant sp-iLys reached its peak lytic activity of 8560 U/mg at pH 6.0 and 30 °C and showed antimicrobial activities against Gram-negative bacteria (Vibrio vulnificus, Vibrio parahemolyticus, and Aeromonas hydrophila) and Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis). In addition, recombinant sp-iLys displayed isopeptidase activity which reached the peak at pH 7.5 and 37 °C with the presence of 0.05 M Na+. In conclusion, this report describes the heterologous expression of recombinant sp-iLys in P. pastoris on a preparative-scale, which possesses lytic activity and isopeptidase activity. This suggests that sp-iLys might play an important role in the innate immunity of S. purpuratus.  相似文献   
29.
Mass spectrometry has emerged as a mainstream technique for label-free proteomics. However, proteomic coverage for trace samples is constrained by adsorption loss during repeated elution at sample pretreatment. Here, we demonstrated superparamagnetic composite nanoparticles functionalized with molecular glues (MGs) to enrich proteins in trace human biofluid. We showed high protein binding (>95 %) and recovery (≈90 %) rates by anchor-nanoparticles. We further proposed a Streamlined Workflow based on Anchor-nanoparticles for Proteomics (SWAP) method that enabled unbiased protein capture, protein digestion and pure peptides elution in one single tube. We demonstrated SWAP to quantify over 2500 protein groups with 100 HEK 293T cells. We adopted SWAP to profile proteomics with trace aqueous humor samples from cataract (n=15) and wet age-related macular degeneration (n=8) patients, and quantified ≈1400 proteins from 5 μL aqueous humor. SWAP simplifies sample preparation steps, minimizes adsorption loss and improves protein coverage for label-free proteomics with previous trace samples.  相似文献   
30.
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