Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 4 de 4
Filter
Add more filters










Database
Publication year range
1.
Sci Rep ; 14(1): 15199, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38956190

ABSTRACT

To address the problems of the conventional composite supporting structures (CCSSs) such as insufficient anti-dislocation performance and deformation capacity, this study used Engineered Cementitious Composite (ECC) lining sections instead of the traditional lining sections and optimized support design parameters, resulting in the development of novel ECC-RC composite supporting structures (ECSSs) of tunnels passing through active fault. The dislocation response characteristics and their parameter sensitivity of the ECSS was revealed by way of 1/25-scale fault dislocation model tests and finite element analysis. The test results show that the mechanical response characteristics and the failure modes of the CCSS and the ECSS are similar under reverse fault dislocation. Compared with the CCSS, the anti-dislocation performance of the ECSS is significantly improved by introducing of the ECC lining and optimizing the design parameters. The vertical deformation of the ECSS and the range of influence under the same dislocation are significantly decreased, and the strain are reduced to different degrees. This phenomenon shows that by improving the material properties, shortening the spacing of aseismatic joints and optimising the thickness of the shock absorption layer, the stress conditions and applicability under deformation of the structure are improved. The ECSS benefits from the crack resistance and toughening effect of fibres, the degree and scope of cracking of the ECSS are significantly reduced compared with those of the CCSS, and internal and external through cracks and local spalling are absent. The results of finite element analysis show that the overall damage degree of the ECSS is decreased and the damage range is increased by decreasing the strength of the surrounding rock in the fault zone. The fault dislocation response pattern of the ECSS varies depending on the fault type. The damage degree caused by different fault types follows the order of normal fault, strike-slip fault, and reverse fault from large to small. However, the damage range caused by the strike-slip fault is significantly larger compared to normal fault and reverse fault. In the design of fault resistance, the surrounding rock conditions of the fault zone and the form of fault dislocation should be considered.

2.
Environ Manage ; 60(4): 747-757, 2017 10.
Article in English | MEDLINE | ID: mdl-28674917

ABSTRACT

In this paper, we analyze the spatio-temporal distribution of vegetation fires in Peninsular Malaysia, Sumatra, and Borneo in the severe El Niño year of 2015, concentrating on the distribution of fires between mineral soils and peatland areas, and between land cover types in peatland areas. The results reveal that 53% of all Moderate Resolution Imaging Spectroradiometer (MODIS) fire detections were recorded in peatlands that cover only 12% of the study area. However, fire occurrence in the peatland areas was highly dependent on land cover type. Pristine peat swamp forests (PSF) experienced only marginal fire activity (30 fire detections per 1000 km2) compared to deforested undeveloped peatlands (831-915 fire detections per 1000 km2). Our results also highlight the extreme fire vulnerability of the southern Sumatran and Bornean peatlands under strong El Niño conditions: 71% of all peatland hotspots were detected in the provinces of South Sumatra and Central Kalimantan, which contain 29% of peatlands in the study area. Degraded PSF and all deforested peatland land cover types, including managed areas, in the two provinces were severely affected, demonstrating how difficult it is to protect even managed drained agricultural areas from unwanted fires during dry periods. Our results thereby advocate rewetting and rehabilitation as the primary management option for highly fire prone degraded undeveloped peatland areas, whenever feasible, as a means to reduce fire risk during future dry episodes.


Subject(s)
Fires/statistics & numerical data , Agriculture/methods , Borneo , Conservation of Natural Resources , Fires/prevention & control , Forestry , Forests , Indonesia , Malaysia , Soil , Wetlands
3.
Sheng Wu Gong Cheng Xue Bao ; 20(4): 516-9, 2004 Jul.
Article in Chinese | MEDLINE | ID: mdl-15968980

ABSTRACT

Rhesus monkeys (5 in each group) were inoculated with recombinant fusion protein of cholera toxin B subunit and multi-valent epitopes of Plasmodium falciparum intranasal or intramuscular (i.m.). Immune-responses and protective effect were evaluated. The antibody titer (Geometry mean) against CTB reached 1:512 (intranasal) and 1:10000 (i.m.) 14 day after 3rd immunization, and antibodies against P. falciparum were also elucidated, the titers in i.m. group were also significantly higher than that in intranasal group. The monkeys were challenged with 1.25 x 10(8) sporozoites of P. cynomolgi, Patent infection was observed in all 5 monkeys in control group inoculated with PBS in 10 - 14 days after challenge. Patent infection was also observed in 5 animals inoculated via intranasal and 2 animals in intramuscular group 19th days after challenge, But the infection last only 4 days in 3 animals in intranasal group and 2 animals in intramuscular group. The results demonstrated that the vaccine candidate could induce protective immune-responses in rhesus monkey against the challenge of P. cynomolgi.


Subject(s)
Cholera Toxin/immunology , Malaria Vaccines/immunology , Malaria/veterinary , Monkey Diseases/prevention & control , Plasmodium cynomolgi , Plasmodium falciparum/immunology , Recombinant Fusion Proteins/immunology , Animals , Antibodies, Bacterial/blood , Antibodies, Protozoan/blood , Cholera Toxin/genetics , Erythrocytes/parasitology , Macaca mulatta , Malaria/prevention & control , Vaccines, Synthetic/immunology
4.
Zhong Yao Cai ; 26(1): 1-3, 2003 Jan.
Article in Chinese | MEDLINE | ID: mdl-12858762

ABSTRACT

Scleroderma guani is an ectoparasitic insect of some borer, especially the larvae or the pupae of longicorn. In Pingyi county of Shandong province, Scleroderma guani was found when it naturally parasitized Xylotrechus grayii in 1980. Passed more than ten years systematic studies, it has been found that this harpactophayeous insect has great boring ability and can be parasitize many hosts. In the fields to release Scleroderma guani for controlling Xylotrechus grayii, Phytoecia rufiventris, Anoplophora glabripennis etc. have achieved good results and kept steady effects. Therefore, spreading Scleroderma guani to control the borer is a new technology in sustaining plant protection.


Subject(s)
Coleoptera/parasitology , Hymenoptera , Pest Control, Biological , Plants, Medicinal , Animals , Evaluation Studies as Topic , Hymenoptera/physiology , Plants, Medicinal/growth & development
SELECTION OF CITATIONS
SEARCH DETAIL
...