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Young-ah WooChang-hee Cho Hyo-jin Kim Jong-soo YangKi-yong Seong 《Microchemical Journal》2002,73(3):299-306
A rapid and nondestructive near infrared (NIR) method using soft independent modeling of class analogy (SIMCA) for the classification of cultivation area (Korea and China) was evaluated and confirmed. Raw, first, and second derivative NIR spectra were compared to develop a robust classification rule. The chemical properties of ginseng samples were also investigated to find out the differences between Korean samples and Chinese samples. These differences make NIR spectroscopic method viable. The average value of each Korean and Chinese ginseng sample for crude fiber, crude protein, starch, and 10 inorganic constituents were measured and compared with F-test and t-test. The inorganic constituents were also measured by induced coupled plasma-atomic emission spectroscopy (ICP-AES). It could be found that the amount of starch and ten inorganic elements for example Na, Mg, P, K, Ca, Mn, Fe, Ni, Cu and Zn in ginseng samples are considerably different based on cultivation area. SIMCA has been applied to the inorganic data to investigate the possibility of ICP-AES as classification tool. However, it was observed that the result was not equal to than NIR spectra data. The overall results showed the availability of NIR method using SIMCA would be adequate for classification of cultivation of ginseng, since NIR spectra includes useful and various information on chemical properties in spite of broad and overlapped bands. 相似文献
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The Raman phonon spectroscopic study shows that the photodimerization of 2,6-dimethyl-p-benzoquinone. In the solid state is initially a homogeneous reaction but later becomes heterogeneous as the product accumulates. The Ion-temperature electronic absorption spectrum reveals that the reaction is phonon assisted by a polaron formed due to a strong electron- phonon coupling in the cxcited 1nπ* state. 相似文献
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Gun Wirtanen Timo Alanko Tiina Mattila-Sandholm 《Colloids and surfaces. B, Biointerfaces》1996,5(6):319-326
Biofilm growth of Bacillus subtilis, Pseudomonas fragi, Pediococcus inopinatus and Listeria monocytogenes was studied on stainless steel surfaces at room and low temperatures to evaluate the results of traditional hygiene measures. The results were compared with those of image analysis of stainless steel surfaces in an epifluorescence microscope. Statistical analyses were carried out to determine the variations between the conventional cultivation swab method, the glycocalyx amount obtained using swabbing, and the values of the areas of the biofilm, slime and cells. As a general rule, old biofilms showed total counts at approximately the same levels as the young biofilm. The results showed that temperature affected the results for all strains except B. subtilis. The strains of Pe. inopinatus and Ps. fragi showed increased attachment at 6°C and L. monocytogenes at 25°C. The biofilm slime was more easily detached than the cells. The results indicated that the traditional swab method is not reliable for the measurement of biofilm formation on surfaces. 相似文献
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《Analytical letters》2012,45(8):1341-1354
The radix of Panax notoginseng is an important herbal resource for clinics, commercial markets, and the health industry worldwide. The quality of P. notoginseng roots is known to be associated with its cultivation age. This study used 1H-nuclear-magnetic-resonance-spectrometry-based metabolic profiling to characterize P. notoginseng roots. Twenty metabolites—including four ginsenosides—contributed to the composition of P. notoginseng according to age. A partial least-squares regression model using a combined data set from two solvent systems was the best predictor of cultivation age. Finally, receiver-operating-characteristic analysis was used to screen potential markers of P. notoginseng root age. These results may be applied to the development of medicinal and nutraceutical products using P. notoginseng roots. 相似文献
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微量元素锌在山药栽培中的应用 总被引:1,自引:0,他引:1
通过田间小区山药栽培实验及室内分析表明:加施锌肥能促进山药幼苗萌发及植株生长速度,加快山药根状块茎的重量;提高块茎名锌素和粗蛋白含量。提示锌肥不仅增加产量同时也改善山药品质。 相似文献
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A “frozen-orbital” diabatic basis has been constructed to study the He+-He resonant charge transfer collision in a closecoupled impact parameter treatment. The Σ—Π rotational couplings are reasonably free from the incorrect asymptotic behaviour (α R?1) Comparison with experiment at large scattering angles demonstrates significant improvement over earlier work. 相似文献
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Microbiological analyses are carried out on clinical, food, feed and environmental samples. The aims of the analyses are diagnostic
or estimation of the safety or the quality of the sample. Important decisions are made on the basis of microbiological analyses.
Little attention, however, is paid to the uncertainty of measurement of microbiological analyses. In microbiological cultivation
techniques the result is obtained by counting individual objects. The normally low number of counted objects strongly affects
the result of the analysis and its uncertainty. Because of the importance of the particle statistical variation to the uncertainty,
the approaches developed for chemical analyses are not directly applicable to microbiology. This paper discusses microbial
analyses and describes a novel guidance document for the estimation of measurement uncertainty in culturing methods [1].
Received: 7 October 2000 Accepted: 8 March 2001 相似文献