994 resultados para Chinese Traditional


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Sustainable water use is seriously compromised in the North China Plain (NCP) due to the huge water requirements of agriculture, the largest use of water resources. An integrated approach which combines the ecosystem model with emergy analysis is presented to determine the optimum quantity of irrigation for sustainable development in irrigated cropping systems. Since the traditional emergy method pays little attention to the dynamic interaction among components of the ecological system and dynamic emergy accounting is in its infancy, it is hard to evaluate the cropping system in hypothetical situations or in response to specific changes. In order to solve this problem, an ecosystem model (Vegetation Interface Processes (VIP) model) is introduced for emergy analysis to describe the production processes. Some raw data, collected by investigating or observing in conventional emergy analysis, may be calculated by the VIP model in the new approach. To demonstrate the advantage of this new approach, we use it to assess the wheat-maize rotation cropping system at different irrigation levels and derive the optimum quantity of irrigation according to the index of ecosystem sustainable development in NCP. The results show, the optimum quantity of irrigation in this region should be 240-330 mm per year in the wheat system and no irrigation in the maize system, because with this quantity of irrigation the rotation crop system reveals: best efficiency in energy transformation (transformity = 6.05E + 4 sej/J); highest sustainability (renewability = 25%); lowest environmental impact (environmental loading ratio = 3.5) and the greatest sustainability index (Emergy Sustainability Index = 0.47) compared with the system in other irrigation amounts. This study demonstrates that application of the new approach is broader than the conventional emergy analysis and the new approach is helpful in optimizing resources allocation, resource-savings and maintaining agricultural sustainability.

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With the rapid increase of the number and influence of floating population in China, it is urgently needed to understand the regional types of China's floating population and their spatial characteristics. After reviewing the current methods for identifying regional types of floating population, this paper puts forward a new composite-index identification method and its modification version which is consisted of two indexes of the net migration rate and gross migration rate. Then, the traditional single-index and the new composite-index identification methods are empirically tested to explore their spatial patterns and characteristics by using China's 2000 census data at county level. The results show: (1) The composite-index identification method is much better than traditional single-index method because it can measure the migration direction and scale of floating simultaneously, and in particular it can identify the unique regional types of floating population with large scale of immigration and emigration. (2) The modified composite-index identification method, by using the share of a region's certain type of floating population to the total in China as weights, can effectively correct the over- or under-estimated errors due to the rather large or small total population of a region. (3) The spatial patterns of different regional types of China's floating population are closely related to the regional differentiation of their natural environment, population density and socio-economic development level. The three active regional types of floating population are mainly located in the eastern part of China with lower elevation, more than 800 mm precipitation, rather higher population densities and economic development levels.

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This study sought to determine the main components (saccharides and phenolic acids) in crude extract of the Chinese herb Tanshen by electrospray ionization Fourier transform ion cyclotron resonant mass spectrometry (ESI-FT-ICR-MS) in negative-ion mode. Eleven compounds were identified as phenolic acids by exact mass measurement and further confirmed by sustained off-resonance irradiation (SORI) CID data. In addition, monosaccharicles and oligosaccharides (n = 2 similar to 5) and a serial of corresponding anionic adducts of saccharide were observed without adding any anions additionally to the extract solution, and the anionic components were unambiguously identified as H2O, HCl, HCOOH, HNO3, C3H6O2, H2SO4 and C5H7NO3 according to the exact mass measurement results.

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Cinnabar, an important traditional Chinese mineral medicine, has been widely used as a Chinese patent medicine ingredient for sedative therapy. However, the pharmaceutical and toxicological effects of cinnabar, especially in the whole organism, were subjected to few investigations. In this study, an NMR-based metabolomics approach has been applied to investigate the toxicological effects of cinnabar after intragastrical administration (dosed at 0.5, 2 and 5 g/kg body weight) on male Wistar rats.

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ESI-MS analytical method was employed to study extracts of unprocessed and processed Radix Paeoniae alba.The results of the experiments prove that different processed methods is making a certain different influence on the contents of chemiacl components in Radix Paeoniae alba.This method is simple and accurate.It can be used for analyse of Traditional Chinese Medicine(TCM).

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Paeoniflorin standard was first investigated by electrospray ionization Fourier transform ion cyclotron resonance tandem mass spectrometry (ESI-FTICR-MS/MS) using a sustained off-resonance irradiation (SORI) collision-induced dissociation (CID) method at high mass resolution. The experimental results demonstrated that the unambiguous elemental composition of product ions can be obtained at high mass resolution. Comparing MS/MS spectra and the experimental methods of hydrogen and deuterium exchange, the logical fragmentation pathways of paeoniflorin have been proposed. Then, the extracts of the traditional Chinese medicine Paeonia lactiflora Pall. were analyzed by high-performance liquid chromatography/electrospray ionization tandem mass spectrometry (HPLC/ESI-MS/MS). By comparison with the ESI-FTICR-MS/MS data of paeoniflorin, the isomers paeoniflorin and albiflorin in Paeonia lactiflora Pall. have been identified using HPLC/MS with CID in an ion trap and in-source CID. Furthermore, using the characteristic fragmentation pathways, the retention times (t(R)) in HPLC and MS/MS spectra, the structures of three other kinds of monoterpene glycoside compounds have been identified on-line without time-consuming isolation.

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This review outlines current progresses in polymer solar cell. Compared to traditional silicon-based photovoltaic (PV) technology, the completely different principle of optoelectric response in the polymer cell results in a novel configuration of the device and more complicated photovoltaic generation process. The conception of bulk-heterojunction (BHJ) is introduced and its advantage in terms of morphology is addressed. The main aspects including the morphology of photoactive layer, which limit the efficiency and stability of polymer solar cell, are discussed in detail. The solutions to boosting up both the efficiency and stability (lifetime) of the polymer solar cell are highlighted at the end of this review.

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Traditional Chinese Medicine (TCM) based on natural products is one important part of the Chinese civilization.Owing to the complexity of the composition,the study on medical effective components and curative effects are very difficult;Fuzi (Radix Aconiti Lateralis Praeparata) has been widely used for cardiotonic and analgesics in China,however,the component-aconitine in which is very toxic and may cause some side-effect.This paper reported the application of electrospray iohization mass spectrometric(ESIMS) technique on study of the compound prescriptions containing fuzi,Renshensini concoction and Baweidihuang concoction,to explore the mechanism of synergy between fuzi and other herbs.From chemical point of view,the detoxification mechanism can be attributed to the hydrolysis of the solubility of toxic diester-alkaloids from concoctions of fuzi.Radix Glycyrrhizae Praeparata,Rhizoma Zingiberis,Radix Ginsengp promote the hydrolysis to produce the less toxic monoester-alkaloids and Fructus Corni reduce the solubility of hypaconitine from fuzi.

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Simple, convenient, sensitive and accurate analytical methods are needed for the structural characterization and identification of alkaloid components in Rhizoma Coptidis in traditional Chinese herbal medicine, which has important bioactivity. In this work, the identification of alkaloid compounds in Rhizoma Coptidis was investigated by obtaining molecular mass information using electrospray ionization mass spectrometry (ESI-MS). Multi-stage tandem mass spectrometric (ESI-MSn) data for the alkaloid compounds were used for detailed structural characterization, then structure information was obtained by comparison of the fragmentation mechanisms of both alkaloids in Rhizoma Coptidis and standard samples of berberine, palmatine, coptisine and jatrorrhizine by MS. Based on the results obtained, the structure of a novel compound was elucidated. The results of the experiments demonstrate that ESI-MSn is a sensitive, selective and effective tool for the rapid determination of alkaloids in Rhizoma Coptidis.