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1.
Front Plant Sci ; 12: 760599, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34721489

RESUMO

Both plant communities and soil microbes have been reported to be correlated with ecosystem multifunctionality (EMF) in terrestrial ecosystems. However, the process and mechanism of aboveground and belowground communities on different EMF patterns are not clear. In order to explore different response patterns and mechanisms of EMF, we divided EMF into low (<0) and high patterns (>0). We found that there were contrasting patterns of low and high EMF in the alpine grassland ecosystem on the Tibetan Plateau. Specifically, compared with low EMF, environmental factors showed higher sensitivity to high EMF. Soil properties are critical factors that mediate the impact of community functions on low EMF based on the change of partial correlation coefficients from 0 to 0.24. In addition, plant community functions and microbial biomass may mediate the shift of EMF from low to high patterns through the driving role of climate across the alpine grassland ecosystem. Our findings will be vital to clarify the mechanism for the stability properties of grassland communities and ecosystems under ongoing and future climate change.

2.
Waste Manag ; 108: 78-105, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32344301

RESUMO

Solid waste materials refer to those municipal or industrial or even domestic wastes that are massively produced during manufacture as well as daily life. A wide variety of solid wastes are generated, but only a few of them are employed in pavement structures. To achieve the task, papers between 2014 and 2019 from top journals which address waste management, waste characterization, and economic and environmental assessment were collected at first. Then, the scope of solid waste materials was narrowed down based on their applications, In the end, six most popular solid waste materials were selected for further study and for the review, namely recycled concrete aggregates, reclaimed asphalt pavement, fly ash, bottom ash, waste rubber, and waste plastics. The reason why only these six solid waste materials are selected is that the rest are neither massively produced not can they be directly used in pavement structures. This review article contains structural properties, treatments, novel researches, environmental analysis, and economic analysis of each solid waste material. The objective of this review article is to provide future researchers with the latest research findings, limitations and improvements in this subject. In conclusion, quite a few novel researchers in terms of workmanship, construction methodology, and treatments are collected for all six materials. Furthermore, an increasing number of findings have proven that most solid waste materials have both environmental and economic benefits when applied in field. Future researchers are encouraged to implement researches on solid waste materials in pavement engineering with consideration of both material properties and environmental/economic effects.


Assuntos
Materiais de Construção , Gerenciamento de Resíduos , Cinza de Carvão , Reciclagem , Resíduos Sólidos
3.
ACS Appl Mater Interfaces ; 10(46): 39983-39991, 2018 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-30383362

RESUMO

The use of biocompatible and biodegradable materials in electronic devices can be an important trend in the development of the next-generation green electronics. In addition, by integrating the advantages of low power consumption, low-cost processing, and flexibility, organic synaptic devices will be promising elements for the construction of brain-inspired computers. However, previously reported electrolyte-gated synaptic transistors are mainly made of non-biocompatible and non-biodegradable electrolytes. Woods are widely considered as one kind of sustainable and renewable materials. We found that wood-derived cellulose nanopapers have ionic conductivity and, therefore, can be used as dielectric materials for organic synaptic transistors. The fabricated wood-derived cellulose nanopapers exhibit decent ionic conductivity of 7.3 × 10-4 S m-1 and a high lateral coupling effective capacitance of 18.65 nF cm-2 at 30 Hz. The laterally coupled organic synaptic transistors using wood-derived cellulose nanopapers as the dielectric layer present excellent transistor performances at the operating voltage below 1.5 V. More significantly, some important synaptic behaviors, such as excitatory postsynaptic current, signal-filtering characteristics, and dendritic integration are successfully simulated in our synaptic transistors. Because the development of electronic devices with biocompatible and biodegradable materials is essential, this work may inspire new directions for the development of "green" neuromorphic electronics.

4.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 26(12): 1420-4, 2012 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-23316628

RESUMO

OBJECTIVE: To investigate the effectiveness of spinal canal decompression with microendoscopic disectomy (MED) and pillar vertebral space insertion through pedicle of vertebral arch for thoracolumbar neglected fracture. METHODS: Between February 2006 and November 2009, 30 patients with thoracolumbar neglected fracture were treated by spinal canal decompression with MED and pillar vertebral space insertion through pedicle of vertebral arch. There were 22 males and 8 females with an average age of 36.2 years (range, 17-58 years). The disease duration was 6 weeks to 14 months with an average of 5.3 months. All patients had single vertebral compression fracture, including T9 in 1 case, T11 in 2 cases, T12 in 5 cases, L1 in 11 cases, L2 in 5 cases, L3 in 5 cases, and L4 in 1 case. The preoperative Cobb angle was (27.5 +/- 7.5) degrees. The preoperative height of vertebrae was (26.67 +/- 5.34) mm. The visual analogue score (VAS) was 5.8 +/- 1.4. According to Wolter classification for spinal canal stenosis, there were 17 cases of grade 1, 10 cases of grade 2, and 3 cases of grade 3. According to Frankel grade, 3 cases were in grade A, 8 cases in grade B, 13 cases in grade C, and 6 cases in grade D. RESULTS: The average operation time was 70 minutes (range, 40-120 minutes) and the average blood loss was 180 mL (range, 100-400 mL). The hematoma occurred in 1 case, and other incisions healed by first intension. No deep vein thrombosis of the lower extremity occurred. All patients were followed up 26 months on average (range, 24-46 months). The Cobb angle and vertebral height at 3 days and last follow-up were significantly improved when compared with ones before operation (P < 0.01). At last followup, the spinal canal stenosis was grade 0 in 27 cases and grade 1 in 3 cases according to Wolter classification. At 24 months after operation, the spinal function was obviously improved; 1 case was in grade A, 1 case in grade B, 3 cases in grade C, 9 cases in grade D, and 16 cases in grade E according to Frankle grade, showing significant differences when compared with preoperative ones (P < 0.05). The VAS score at 1 month after operation was significantly higher than that before operation (P < 0.01), then the score showed downtrend along with time, and it was significantly lower at 24 months after operation than before operation (P < 0.01). CONCLUSION: Spinal canal decompression with MED and pillar vertebral space insertion for thoracolumbar neglected fracture has short surgical time, less blood loss, and satisfactory reduction, but higher technical requirement is necessary for MED.


Assuntos
Descompressão Cirúrgica/métodos , Vértebras Lombares/lesões , Próteses e Implantes , Fraturas da Coluna Vertebral/cirurgia , Vértebras Torácicas/lesões , Adolescente , Adulto , Transplante Ósseo/métodos , Descompressão Cirúrgica/instrumentação , Discotomia/métodos , Endoscopia , Feminino , Seguimentos , Fixação Interna de Fraturas , Humanos , Vértebras Lombares/cirurgia , Masculino , Pessoa de Meia-Idade , Vértebras Torácicas/cirurgia , Resultado do Tratamento , Adulto Jovem
5.
J Environ Sci (China) ; 20(3): 339-46, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18595402

RESUMO

Abies fabric forest in the eastern slope of Gongga mountain is one type of subalpine dark coniferous forests of southwestern China. It is located on the southeastern edge of the Qinghai-Tibet plateau and is sensitive to climatic changes. A process-oriented biogeochemical model, Forest-DNDC, was applied to simulate the effects of climatic factors, temperature and precipitation changes on carbon characteristics, and greenhouse gases (GHGs) emissions in A. fabric forest. Validation indicated that the Forest-DNDC could be used to predict carbon characteristics and GHGs emissions with reasonable accuracy. The model simulated carbon fluxes, soil carbon dynamics, soil CO2, N2O, and NO emissions with the changes of temperature and precipitation conditions. The results showed that with variation in the baseline temperature from -2 degrees C to +2 degrees C, the gross primary production (GPP) and soil organic carbon (SOC) increased, and the net primary production (NPP) and net ecosystem production (NEP) decreased because of higher respiration rate. With increasing baseline precipitation the GPP and NPP increased slightly, and the NEP and SOC showed decreasing trend. Soil CO2 emissions increased with the increase of temperature, and CO2 emissions changed little with increased baseline precipitation. With increased temperature and decreased baseline temperature, the total annual soil N2O emissions increased. With the variation of baseline temperature from -2 degrees C to +2 degrees C, the total annual soil NO emissions increased. The total annual N2O and NO emissions showed increasing trends with the increase of precipitation. The biogeochemical simulation of the typical forest indicated that temperature changes strongly affected carbon fluxes, soil carbon dynamics, and soil GHGs emissions. The precipitation was not a principal factor affecting carbon fluxes, soil carbon dynamics, and soil CO2 emissions, but changes in precipitation could exert strong effect on soil N2O and NO emissions.


Assuntos
Abies/crescimento & desenvolvimento , Carbono/análise , Efeito Estufa , Temperatura , Dióxido de Carbono/análise , Ecossistema , Óxido Nítrico/análise , Óxido Nitroso/análise , Chuva , Estações do Ano , Tibet
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