Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
J Environ Manage ; 370: 122501, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39299129

RESUMO

As an important part of the ecosystem, saline-alkali soils are in urgent need of efficient and environmentally friendly soil conditioners. Biochar and wood vinegar are regarded as organic soil improvement and plant growth regulators to improve soil physicochemical properties and promote crop growth. However, the mechanism of how inorganic phosphorus bacteria increase phosphorus when biochar and wood vinegar applied to saline-alkali soils is not clear. Herein, the present study was designed to investigate the effects of biochar and wood vinegar with different rates on physicochemical properties of saline-alkali soils and inorganic phosphorus bacteria diversities and to discuss the mechanism of biochar and wood vinegar on available phosphorus by pot experiments. The application of biochar and wood vinegar exhibited an effect on the decrease in pH and salt contents and the increase in soil porosity, soil nutrients, and hundred-grain weight of rice. The 600 kg ha-1 biochar and 1800 kg ha-1 wood vinegar group showed the most significant increment in available phosphorus, alkaline phosphatase, acid phosphatase, and neutral phosphatase activities, with the increases of 49.24%, 40.35%, 48%, and 149%, respectively. The 600 kg ha-1 biochar and 1200 kg ha-1 wood vinegar group significantly enhanced microbial biomass phosphorus concentrations by 41.29%. Moreover, biochar and wood vinegar shifted inorganic phosphorus bacteria composition structure and promoted its diversities, more so at a higher rate of wood vinegar application. The dominant species of inorganic phosphorus bacteria were Proteobacteria, Gammaproteobacteria, Alphaproteobacteria, Pseudomonas, and Rhizobium in saline-alkali soils. The Alphaproteobacteria and Hydrogenophaga were the key microorganisms reducing pH and salt contents and increasing available phosphorus contents in saline-alkali soils. In conclusion, the application of biochar and wood vinegar was a useful strategy to improve saline-alkali soils.

2.
Small ; : e2308739, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38054629

RESUMO

Building of metal-organic frameworks (MOFs) homogeneous hydrogels made by spontaneous crystallization remains a significant challenge. Inspired by anisotropically structured materials in nature, an oriented super-assembly strategy to construct micro-scale MOFs superstructure is reported, in which the strong intermolecular interactions between zirconium-oxygen (Zr─O) cluster and glutamic acid are utilized to drive the self-assembly of flexible nanoribbons into pumpkin-like microspheres. The confined effect between water-flexible building blocks and crosslinked hydrogen networks of superstructures achieved a mismatch transformation of MOFs powders into homogeneous hydrogels. Importantly, the elastic and rigid properties of hydrogels can be simply controlled by precise modulation of coordination and self-assembly for anisotropic superstructure. Experimental results and theoretical calculations demonstrates that MOFs anisotropic superstructure exhibits dynamic double networks with a superior water harvesting capacity (119.73 g g-1 ) accompanied with heavy metal removal (1331.67 mg g-1 ) and strong mechanical strength (Young's modulus of 0.3 GPa). The study highlights the unique possibility of tailoring MOFs superstructure with homogeneous hydrogel behavior for application in diverse fields.

3.
Materials (Basel) ; 17(16)2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39203298

RESUMO

Concrete coatings show significant promise in shielding concrete substrates from corrosion by effectively resisting harmful ions and moisture. Thanks to their practicality, high efficiency, and cost-effectiveness, coatings are considered a potent technique for enhancing the chloride resistance of reinforced concrete structures. Over recent decades, extensive research has concentrated on employing coatings to bolster concrete's ability to withstand chloride penetration. This paper provides a holistic review of the current studies on chloride infiltration in concrete surfaces treated with coating materials, primarily focused on chloride resistance improvement efficiency and chloride transport modeling. Firstly, by comparing the functions of assorted coatings, four inherent protection mechanisms are summarized and elaborated thoroughly. Afterwards, the chloride resistance improvement efficiency of assorted coatings reported in current studies are reviewed and compared in great detail, with a specific focus on inorganic, organic, and organic-inorganic composite coatings. Furthermore, the theoretical research about methodologies for chloride transport behavior prediction is summarized. Finally, this paper outlines the potential research directions in this field and the theoretical, technical, and practical application challenges. This review not only identifies critical areas necessitating further investigation and problem-solving in this domain but also aids in selecting appropriate coating materials and refining corrosion management strategies.

4.
Bioresour Technol ; 412: 131404, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39222858

RESUMO

Photosynthetic biohybrid systems (PBSs) composed of semiconductor-microbial hybrids provide a novel approach for converting light into chemical energy. However, comprehending the intricate interactions between materials and microbes that lead to PBSs with high apparent quantum yields (AQY) is challenging. Machine learning holds promise in predicting these interactions. To address this issue, this study employs ensemble learning (ESL) based on Random Forest, Gradient Boosting Decision Tree, and eXtreme Gradient Boosting to predict AQY of PBSs utilizing a dataset comprising 15 influential factors. The ESL model demonstrates exceptional accuracy and interpretability (R2 value of 0.927), offering insights into the impact of these factors on AQY while facilitating the selection of efficient semiconductors. Furthermore, this research propose that efficient charge carrier separation and transfer at the bio-abiotic interface are crucial for achieving high AQY levels. This research provides guidance for selecting semiconductors suitable for productive PBSs while elucidating mechanisms underlying their enhanced efficiency.


Assuntos
Aprendizado de Máquina , Fotossíntese , Semicondutores , Fotossíntese/fisiologia
5.
Ying Yong Sheng Tai Xue Bao ; 34(4): 1123-1129, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37078333

RESUMO

Taking straws of corn, wheat, and millet as raw materials, we pretreated them with alkaline hydrogen peroxide, and then hydrolyzed by cellulase and xylanase. We selected the total sugar content in the hydrolysate as the indicator to evaluate the hydrolysis of the straws from three crop species, and further optimized the conditions. Then, the hydrolysates of three types of crop straws were used as carbon source for Chlorella sorokiniana culture to assess their effects on microalgal cultivation. The results showed that the optimal hydrolysis conditions for the three crop straws were identified as solid-liquid ratio of 1:15, temperature of 30 ℃, and treatment time of 12 h. Under such optimal condition, the total sugar contents increased up to 1.677, 1.412, and 1.211 g·L-1 in the corn, millet and wheat straw hydrolysate, respectively. The hydrolysates from the three crop straw could significantly increase both algal biomass and lipid content of C. sorokiniana. Corn straw hydrolysate had the best effect, with high levels of algal biomass (1.801 g·L-1) and lipid content (30.1%). Therefore, we concluded that crop straw hydrolysates as carbon source could significantly promote microalgal biomass and lipid enrichment. The results could lay the foundation for the efficient conversion and utilization of straw lignocellulose raw materials, provide new knowledge for the resource utilization of agricultural wastes, as well as the theoretical basis for the efficient cultivation of microalgae using crop straw hydrolysates.


Assuntos
Chlorella , Hidrólise , Lipídeos , Carbono , Açúcares , Biomassa
6.
Comput Intell Neurosci ; 2022: 3624413, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35720945

RESUMO

In order to improve the operation efficiency of the innovation and entrepreneurship integration system of college students, this document proposes to formulate and implement the innovation and entrepreneurship integration system of college students based on "Internet technology." The web front end is implemented by Django technology, the back end is developed by Apache server pycharm, the database is written in Python, and the database is MySQL. The system meets the expected objectives of implementing, monitoring, and managing innovation and entrepreneurship projects. How the system realizes the functions of repeated comparison projects, easy tracking projects, and fast search, and how managers can make progress at any time. By creating different account function permissions, the system realizes the login, declaration, management, and other functions required by the users of the innovation and entrepreneurship project management system. It is very suitable for college students to improve the project application, information review, and application process. At the same time, it is helpful to supervise and select teachers and greatly improve management efficiency. The test results show that the minimum values of 30, 80, and 150 simulated users in the system performance test are 4, 5, and 7, respectively. The maximum users of the system performance test model are 30, 80, 150, 64, 284, and 398. The system performance tests are taken under the conditions of 30, 80, and 150 user bandwidth, with the results of 113/min, 104/min, and 90/min. The system basically meets the daily work management standards and fully achieves the expected system design goals. The development and use of this system are related to the development of college students' innovation and entrepreneurship project management and have a clear reference for the development of innovation and entrepreneurship project management systems similar to manage workflow in the future.


Assuntos
Empreendedorismo , Internet das Coisas , Humanos , Estudantes , Tecnologia/educação
7.
Sci Total Environ ; 758: 143883, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33338792

RESUMO

Mercury (Hg) is toxic and can affect human health through soil entering food chain. Spinach absorb easily heavy metals. Corn stover biochar can improve soil structure and physicochemical property. This study wanted to establish a Hg-corn stover biochar-soil-spinach model including 1 control group (without HgCl2 and corn stover biochar) and 24 treatment groups (with HgCl2 or/and corn stover biochar). Hg concentration was 0, 1, 2, 4, and 6 mg kg-1, respectively. Corn stover biochar contents were 0%, 1%, 3%, 5%, and 7% w/w, respectively. The results showed that residual Hg concentrations was the largest and water soluble and exchangeable Hg as well as carbonate bound Hg concentrations were the lowest among five Hg forms. Hg concentrations in four Hg treatment groups were higher than the control group in dose-dependent manner. The deposition of 6 mg kg-1 Hg was the highest. Corn stover biochar decreased Hg migration from soil to leaching solution and spinach, and passivation effect of 7% concentration of corn stover biochar was the best. Besides, corn stover biochar relieved the increase of methyl Hg caused by Hg in soil. Moreover, Hg concentration in roots was the highest and Hg concentration in stems was the lowest in spinach. Furthermore, Hg absorbed by roots was more than the sum of Hg absorbed by stems and leaves. In addition, we also found that the measured soil Hg concentrations were coincided with the predicted soil Hg concentrations under 1, 2, and 4 mg kg-1 Hg concentrations, except 2 mg kg-1 Hg at 7% C. Under 6 mg kg-1 Hg concentration, measured soil Hg concentrations was lower than that of the predicted soil Hg concentrations. Taken together, our findings indicated that corn stover biochar can increase edible safety of spinach by immobilizing Hg in soil and be used as an organic amendment.


Assuntos
Mercúrio , Poluentes do Solo , Carvão Vegetal , Humanos , Mercúrio/análise , Solo , Poluentes do Solo/análise , Spinacia oleracea , Zea mays
8.
Sci Rep ; 10(1): 14375, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32873826

RESUMO

Over the past 30 years, human disturbance and habitat fragmentation have severely endangered the survival of common wild rice (Oryza rufipogon Griff.) in China. A better understanding of the genetic structure of O. rufipogon populations will therefore be useful for the development of conservation strategies. We examined the diversity and genetic structure of natural O. rufipogon populations at the national, provincial, and local levels using simple sequence repeat (SSR) markers. Twenty representative populations from sites across China showed high levels of genetic variability, and approximately 44% of the total genetic variation was among populations. At the local level, we studied fourteen populations in Guangxi Province and four populations in Jiangxi Province. Populations from similar ecosystems showed less genetic differentiation, and local environmental conditions rather than geographic distance appeared to have influenced gene flow during population genetic evolution. We identified a triangular area, including northern Hainan, southern Guangdong, and southwestern Guangxi, as the genetic diversity center of O. rufipogon in China, and we proposed that this area should be given priority during the development of ex situ and in situ conservation strategies. Populations from less common ecosystem types should also be given priority for in situ conservation.


Assuntos
Produtos Agrícolas/genética , Espécies em Perigo de Extinção , Genes de Plantas , Variação Genética , Oryza/genética , Alelos , China , DNA de Plantas/genética , Ecossistema , Evolução Molecular , Fluxo Gênico , Repetições de Microssatélites/genética , Reação em Cadeia da Polimerase , Análise de Componente Principal
9.
Artigo em Chinês | MEDLINE | ID: mdl-18349502

RESUMO

Plant seed oil is the major source of many fatty acids for human nutrition, and also one of industrial feedstocks. Recent advances in understanding of the basic biochemistry of seed oil biosynthesis, coupled with cloning of the genes encoding the enzymes involved in fatty acid modification and oil accumulation, have set the stage for the metabolic engineering of oilseed crops that produce "designer" plant seed oils with the improved nutritional values for human being. In this review we provide an overview of seed oil biosynthesis/regulation and highlight the key enzymatic steps that are targets for gene manipulation. The strategies of metabolic engineering of fatty acids in oilseeds, including overexpression or suppression of genes encoding single or multi-step biosynthetic pathways and assembling the complete pathway for the synthesis of long-chain polyunsaturated fatty acids (e.g. arachidonic acid, eicosapentaenoic acid and docosahexaenoic acid) are described in detail. The current "bottlenecks" in using common oilseeds as "bioreactors" for commercial production of high-value fatty acids are analyzed. It is also discussed that the future research focuses of oilseed metabolic engineering and the prospects in creating renewable sources and promoting the sustainable development of human society and economy.


Assuntos
Engenharia Genética/métodos , Óleos de Plantas/metabolismo , Sementes/metabolismo , Ácidos Graxos/genética , Ácidos Graxos/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Sementes/genética
10.
Front Microbiol ; 8: 2208, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29176968

RESUMO

Coniothyrium minitans is an important mycoparasite of Sclerotinia sclerotiorum. In addition, it also produces small amounts of antifungal substances. ZS-1TN1812, an abnormal mutant, was originally screened from a T-DNA insertional library. This mutant showed abnormal growth phenotype and could significantly inhibit the growth of S. sclerotiorum when dual-cultured on a PDA plate. When spraying the filtrate of ZS-1TN1812 on the leaves of rapeseed, S. sclerotiorum infection was significantly inhibited, suggesting that the antifungal substances produced by this mutant were effective on rapeseed leaves. The thermo-tolerant antifungal substances could specifically suppress the growth of S. sclerotiorum, but could not significantly suppress the growth of another fungus, Colletotrichum higginsianum. However, C. higginsianum was more sensitive to proteinous antibiotics than S. sclerotiorum. The T-DNA insertion in ZS-1TN1812 activated the expression of CmSIT1, a gene involved in siderophore-mediated iron transport. It was also determined that mutant ZS-1TN1812 produced hypha with high iron levels. In the wild-type strain ZS-1, CmSIT1 was expressed only when in contact with S. sclerotiorum, and consistent overexpression of CmSIT1 showed similar phenotypes as ZS-1TN1812. Therefore, activated expression of CmSIT1 leads to the enhanced antifungal ability, and CmSIT1 is a potential gene for improving the control ability of C. minitans.

12.
Sheng Wu Gong Cheng Xue Bao ; 29(5): 630-45, 2013 May.
Artigo em Chinês | MEDLINE | ID: mdl-24010361

RESUMO

Palmitoleic acid (16:1delta9), an unusual monounsaturated fatty acid, is highly valued for human nutrition, medication and industry. Plant oils containing large amounts of palmitoleic acid are the ideal resource for biodiesel production. To increase accumulation of palmitoleic acid in plant tissues, we used a yeast (Saccharomyees cerevisiae) acyl-CoA-delta9 desaturase (Scdelta9D) for cytosol- and plastid-targeting expression in tobacco (Nicotiana tabacum L.). By doing this, we also studied the effects of the subcellular-targeted expression of this enzyme on lipid synthesis and metabolism in plant system. Compared to the wild type and vector control plants, the contents of monounsaturated palmitoleic (16:1delta9) and cis-vaccenic (18:1delta11) were significantly enhanced in the Scdelta9D-transgenic leaves whereas the levels of saturated palmitic acid (16:0) and polyunsaturated linoleic (18:2) and linolenic (18:3) acids were reduced in the transgenics. Notably, the contents of 16:1delta9 and 18:1delta11 in the Scdelta9D plastidal-expressed leaves were 2.7 and 1.9 folds of that in the cytosolic-expressed tissues. Statistical analysis appeared a negative correlation coefficient between 16:0 and 16:1delta9 levels. Our data indicate that yeast cytosolic acyl-CoA-delta9 desaturase can convert palmitic (16:0) into palmitoleic acid (16:1delta9) in high plant cells. Moreover, this effect of the enzyme is stronger with the plastid-targeted expression than the cytosol-target expression. The present study developed a new strategy for high accumulation of omega-7 fatty acids (16:1delta9 andl8:1delta11) in plant tissues by protein engineering of acyl-CoA-delta9 desaturase. The findings would particularly benefit the metabolic assembly of the lipid biosynthesis pathway in the large-biomass vegetative organs such as tobacco leaves for the production of high-quality biodiesel.


Assuntos
Ácidos Graxos Dessaturases/metabolismo , Ácidos Graxos Monoinsaturados/metabolismo , Nicotiana/metabolismo , Plantas Geneticamente Modificadas , Saccharomyces cerevisiae/enzimologia , Ácidos Graxos Dessaturases/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Nicotiana/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA