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1.
Huan Jing Ke Xue ; 45(1): 364-375, 2024 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-38216486

RESUMO

In this study, we sought to quantify the effect of planting structure change on fertilizer input and environmental cost in Chongqing and develop scientific and rational strategies for chemical fertilizer reduction. Based on the crop fertilizer quota standard and large sample farmer survey data under the medium productivity level in Chongqing, we evaluated and analyzed the application reduction potential and environmental benefits of fertilizer with the difference method and life cycle assessment. The results showed that:① since Chongqing became a municipality directly under the central government (1997), Chongqing crop planting structure had greatly changed, and the proportion of food crop (rice, corn, wheat, bean, and potato) decreased by 21%. The area of fruits and vegetables increased from 3.36×105 hm2 to 1.05×106 hm2, and their proportion increased by 20%. ② Nearly 55% of fertilizers had been consumed by vegetable (37%) and citrus production systems, and 11%, 12%, and 12% of fertilizers were consumed by rice, corn, and potato, respectively. ③ The total fertilizer reduction of the Chongqing planting industry could reach up to 1.69×105 tons during the period of "the 14th Five-Year Plan," with a fertilizer reduction potential of 18.6%. The fertilizer reduction potential (reduction amount) of rice, corn, citrus, and vegetables would reach 0.3% (2.9×102 tons), 12% (1.45×104 tons), 21% (3.65×104 tons), and 30% (1.18×105 tons), respectively. On the other hand, the rape system was insufficient in phosphorus potassium fertilizers, and the corn tended to be insufficient in potash fertilizer. ④ The current production level was low, and the nitrogen loss, greenhouse gas emissions, and eutrophication potential in the planting industry of Chongqing reached 1.81×105 tons (N), 1.43×107 tons (CO2-eq), and 1.74×105 tons (PO4-eq). With the increase in the realization degree of the crop quota standard (60%-100%), the reactive nitrogen loss, greenhouse gas emissions, and eutrophication potential decreased by 14.9%-24.9%, 10.1%-16.7%, and 13.8%-23%, respectively. The structure of the planting industry in Chongqing significantly changed, the total fertilizer consumption in Chongqing tended to decline gradually, and the fertilization intensity of commercial crops stayed at a high level. The agricultural fertilizer reduction potential and the reactive nitrogen and greenhouse gas emission reduction potential were large, especially for citrus and vegetable production systems. However, it is also necessary to pay attention to insufficient corn potash fertilizer and rape phosphorus potassium fertilizer investment and carry out collaborative promotion of fertilizer reduction.


Assuntos
Gases de Efeito Estufa , Oryza , Fertilizantes/análise , Gases de Efeito Estufa/análise , Agricultura/métodos , Verduras , Nitrogênio/análise , Fósforo/análise , Potássio , China , Solo/química , Óxido Nitroso/análise
2.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 28(2): 177-81, 2008 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-18386587

RESUMO

In order to advance the treatment of Alzheimer's disease with active ingredients of Chinese herbal medicines and the research on these ingredients and their effective targets in treating the disease, the relative representative literatures published in recent years were reviewed and summarized in this paper.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Fitoterapia/métodos , Alcaloides , Medicamentos de Ervas Chinesas/química , Ginkgo biloba/química , Ginsenosídeos/uso terapêutico , Humanos , Fitoterapia/tendências , Salvia miltiorrhiza/química , Sesquiterpenos/uso terapêutico
3.
Nan Fang Yi Ke Da Xue Xue Bao ; 27(12): 1830-3, 2007 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-18158995

RESUMO

OBJECTIVE: To establish a method for fingerprinting of Fuzhisan (FZS, a traditional Chinese medicinal preparation) using high-performance liquid chromatography with ultraviolet and evaporative light scattering detector (HPLC-UV/ELSD) to allow simultaneous determination of 5 major constituents in the preparation. METHODS: HPLC-UV/ELSD analysis was performed on water AlltechC18 column (5 microm, 4.6 mm x 250 mm) with a mixture of acetonitrile (A) and 0.1% acetice acid water (B) as the mobile phase. The solvent A gradient for elution was 0, 12%; 25, 20%; 30, 20%; 75, 30%; 105, 40%; 120, 80%; 130, 12%, with the flow rate of 1.0 ml/min; and the column temperature at 30 degrees . The detective wavelength was 335 nm, drift tube temperature was 80 degrees , pressure of nebulizer gas was 25 psi. The similarities between the HPLC-UV/ELSD fingerprints of the 12 extracts were calculated using similarity evaluation software. RESULTS: The fingerprint of FZS was established and the 5 major constituents were identified. The complementarity between the fingerprints of UV and ELSD was analyzed, showing good correlation between 12 batches of FZS. CONCLUSION: The method for fingerprinting can simultaneously characterize the main chemical constituents in FZS and allows stable, effective and comprehensive quality control and evaluation of FZS for a single sample.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Espalhamento de Radiação , Medicamentos de Ervas Chinesas/normas , Luz , Controle de Qualidade , Raios Ultravioleta
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