RESUMO
Palladium is a key catalyst invaluable to many industrial processes and fine-chemical synthesis. Although recent progress has allowed the synthesis of Pd nanoparticles with various shapes by using different techniques, the facile synthesis of Pd nanocrystals and turning them into a highly active, selective, and stable catalyst systems still remain challenging. Herein, we report the highly selective one-pot synthesis of monodisperse Pd cluster nanowires in aqueous solution; these consist of interconnected nanoparticles and may serve as highly active catalysts because of the enrichment of high index facets on the surface, including {443}, {331}, and {221} steps. For the first time, carbon nanotube and γ-Al(2)O(3) immobilized Pd cluster nanowires showed highly enhanced catalytic performance in the liquid-phase selective hydrogenation of cinnamaldehyde and gas-phase hydrogenation of 1,3butadiene relative to immobilized Pd icosahedra and nanocubes, as well as commercial Pd catalysts.
Assuntos
Nanopartículas/química , Nanofios/química , Paládio/química , Catálise , Hidrogenação , Nanotecnologia , Propriedades de SuperfícieRESUMO
The issues of disordering production and non-standard pesticide application are common in the production of Chinese herbal medicines. Aimed to above problems, research groups built the pollution-free and precision cultivation system of medicinal plants. This system mainly included the precise site selection of medicinal plants based on the GIS technology, modern omics-assisted breeding, metagenomics guiding the soil complex improvement, and the precise field management based on rational application of fertilizer and comprehensive control of disease. At present, the production and distribution of medicinal plants were performed in the many poor counties of the whole nation. The breeding platform of resistant varieties was built, and certificates of new and well-bred varieties were received, in the base of genetic backgrounds of the original species of medicinal plants. The disease incidences were declined after application of these resistant varieties. Additionally, chemical pesticide consumption of medicinal plants (such as Panax ginseng, P. notoginseng, Salvia miltiorrhiza, P. quinquefolium, Schisandra chinensis, Platycodon grandiflorum and P. grandiflorus etc.) reduced by 20%-80% based on the genetic testing technologies of plant diseases and insect pests and safety evaluation of pollution-free pesticides. The application of pollution-free and precision cultivation system of Chinese herbal medicines achieve significantly social, economic and ecological benefits.
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Pt-Pd bimetallic alloy nanostructures with highly selective morphologies such as cube, bar, flower, concave cube, and dendrite have been achieved through a facile one-pot solvothermal synthesis. The effects of shape-controllers (sodium dodecyl sulfate (SDS), ethylenediamine-tetraacetic acid disodium salt (EDTA-2Na), NaI) and solvents (water/DMF) on the morphologies were systematically investigated. The electrocatalytic activities of these Pt-Pd alloy nanostructures toward formic acid oxidation were tested. The results indicated that these alloy nanocrystals exhibited enhanced and shape-dependent electrocatalytic activity toward formic acid oxidation compared to commercial Pt black and Pt/C catalysts.
RESUMO
DNA marked-assisted selection of medicinal plants accelerated the breeding and promotion of new cultivars, and guaranteed the healthy development of Chinese medicinal materials industry. The first disease-resistant cultivar of notoginseng, namely "Miaoxiang Kangqi 1", served as the object of study. We evaluated the Kangqi's resistance of seeds, seedlings and root against the pathological bacteria (Fusarum oxysporum) of root rot. Compared to the traditional cultivars, the disease index of notoginseng seeds declined by 52.0% after inoculation for seven days; the death rate of seedlings and disease index of root respectively decreased by 72.1% and 62.4% after inoculation for 25 days. Additionally, the growth inhibition ratio of notoginseng seeds and seedlings declined after inoculation. The seeds, seedlings and roots of "Miaoxiang Kangqi 1" showed significantly resistant to root rot. The evaluation of disease-resistance of Kangqi provided the basis for the popularization of new cultivar and guaranteed the favoring conduct of notoginseng pollution-free cultivation.
RESUMO
DNA marker-assisted selection of medicinal plants is based on the DNA polymorphism, selects the DNA sequences related to the phenotypes such as high yields, superior quality, stress-resistance and so on according to the technologies of molecular hybridization, polymerase chain reaction and high-throughput sequencing, and assists the breeding of new cultivars. This study bred the first disease-resistant cultivar of notoginseng "Miaoxiang Kangqi 1" using the technology of DNA marker-assisted selection of medicinal plants and systematic breeding. The disease-resistant cultivar of notoginseng contained 12 special SNPs based on the analysis of Restriction-site Associated DNA Sequencing (RAD-Seq). Among the SNP (record_519688) was related to the root rot-resistant characteristics, which indicated this SNP could serve as genetic markers of disease-resistant cultivars and assist the systematic breeding. Compared to the conventional cultivated cultivars, the incidence rate of root-rot and rust-rot in notoginseng seedlings decreased by 83.6% and 71.8%, respectively. The incidence rate of root-rot respectively declined by 43.6% and 62.9% in notoginseng cultivation for 2 and 3 years compared with those of the conventional cultivated cultivars. Additionally, the potential disease-resistant groups were screened based on the relative SNP, and this model enlarged the target groups and advanced the breeding efficiency. DNA marker-assisted selection of medicinal plants accelerated the breeding and promotion of new cultivars, and guaranteed the healthy development of Chinese medicinal materials industry.
RESUMO
In this study, the Geographic Information System for Global Medicinal Plants (GMPGIS) was used to assess the global production and ecological adaptation of Panax notoginseng. Based on climate factors and soil types of P.notoginseng from 326 sampling sites, which cover both traditional and current major producing regions, as well as on the results of the ecological similarity computing analysis, we obtained the maximum ecological similarity areas for P.notoginseng worldwide. The results indicated that China was the most suitable ecological and cultivated area globally for P.notoginseng, accounting for more than 70% of the total cultivated area in the world. The United States, Brazil, Portugal, and other 22 countries also had a small amount of potential suitable producing area. China has eight potential suitable producing provinces, including Yunnan, Fujian, Guangxi, Guizhou, etc. The prediction is consistent with the new district of P.notoginseng reported in recent years, which verifies the accuracy of the prediction of GMPGIS. We conducted a literature analysis on resource regeneration and quality ecology on P.notoginseng, and summarized the cultivation, wild tending models, and effects of environmental factors on the quality of P. notoginseng. The results provide scientific basis for selection of P.notoginseng, as well as the introduction, cultivation, and production of P. notoginseng worldwide.