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111.
Thd H 3 + molecular ion plays an important role in the chemistry of astronomical objects as it protonates the neutral species. The authors have recently calculated the partition functions of H 3 + which may be used to compute the equilibrium constants for the chemical reaction H2+H2 +H 3 + +H. In this short communication we have calculated the equilibrium constants for the temperature range from 500 to 8000 K. The results are also presented in the polynomial form.  相似文献   
112.
The screw anchor piles are installed in ground by screwing which is done with the help of torque motors. In this paper, the lateral load capacity of screw anchor piles is examined through an experimental investigation carried on model piles embedded in dry sand. The tests were carried on screw anchor piles with different number of helices provided in continuation. Lateral loads were applied at different height above the soil surface. The embedment length of screw anchor piles was also varied to study the behaviour of screw anchor piles under lateral loads. Some tests were conducted on plain shaft pile to compare the lateral load capacity of screw anchor piles with that of plain shaft piles. An empirical equation for computation of lateral loads has been developed considering lateral resistance, bearing resistance, uplift resistance and lateral resistance offered by soil in pile on the basis of experimental results. A theoretical model for predicting lateral load capacity of screw anchor piles in dry sand, consistent with the experimental findings has been developed in this study.  相似文献   
113.
Mahata  Dinabandhu  Shekhar  Sulochana 《GeoJournal》2022,87(4):675-682

In the twenty-first century, land use changes, massive expansion of urbanization, population growth, economic crisis, environmental issues are the main challenges of developing countries. Climate change and its effects on human health are the major concerns for the different age groups of the population. The study delved into the causes associated with climate change and climate change-related myriad health impacts on the study population. This study has used a concurrent mixed-method research design. The quantitative and qualitative data were collected from the study area. Perception and knowledge about climate change and its consequences on health was based on a quantitative approach of Bi-variate analysis and Chi-Square test and Fisher’s exact test; this study also used qualitative data analysis. Study results show that most respondents pointed out that temperature increases throughout the year and 90% of the respondents reported that rainfall pattern has also changed. Similarly, 65% of respondents agreed in their statements in favour of increased natural calamities in this region. The study findings show that more than 40% of population faces dengue fever and 10% of people also suffer from malaria. More than 60% of the urban population suffered from asthma. Similarly, more than 70% of the population also got affected by cold and cough due to weather variability. Focus Group Discussion (FGD) and In-depth interviews of the participants also affirmed the fact that climate variability induced diseases and health problems in Kolkata Metropolitan areas. Urban residents perceived that excessive urbanization contributes to the changes in regional climate and human health. The study will encourage the policy-makers and local government to mitigate adverse health effects driven by climate change in the Kolkata Metropolitan Region.

  相似文献   
114.
Natural Hazards - The agricultural land of the whole world is deteriorating due to the loss of top fertile soil reducing agricultural productivity and groundwater availability. Mainly, natural...  相似文献   
115.
Chandra  Sagarika  Kumar  Praveen  Siingh  Devendraa  Roy  I.  Victor  N. Jeni  Kamra  A. K. 《Natural Hazards》2022,110(1):57-68

Physical phenomena observed before strong earthquakes have been reported for centuries. Precursor signals, which include radon anomalies, electrical signals, water level changes and ground lights near the epicenter, can all be used for earthquake prediction. Anomalous negative signals observed by ground-based atmospheric electric field instruments under fair weather conditions constitute a novel earthquake prediction approach. In theory, the abnormal radiation of heat before an earthquake produces fair weather around the epicenter. To determine the near-epicenter weather conditions prior to an earthquake, 81 global earthquake events with magnitudes of 6 or above from 2008 to 2021 were collected. According to Harrison's fair weather criteria, in 81.48% of all statistical cases, the weather was fair 6 h before the earthquake; in 62.96% of all cases, the weather was fair 24 h before the event. Moreover, most of these cases without fair weather several hours before the earthquake were near the sea. Among the 37 inland earthquakes, 86.49% were preceded by 6 h of fair weather, and 70.27% were preceded by fair weather for 24 h. We conclude that the weather near the epicenter might be fair for several hours before a strong earthquake, especially for inland events.

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116.
Natural Hazards - Avalanche forecasting is carried out using physical as well as statistical models. All these models have certain limitations associated with their mathematical formulation that...  相似文献   
117.
Chen  Ruifeng  Congress  Surya Sarat Chandra  Cai  Guojun  Zhou  Ruixian  Xu  Jingmin  Duan  Wei  Liu  Songyu 《Acta Geotechnica》2023,18(2):1039-1056
Acta Geotechnica - Soft clay generally cannot be directly used as subgrade material due to its poor engineering characteristics. The application of rice husk ash (RHA) for the solidification of...  相似文献   
118.
Prakash  Kumar Ravi  Nigam  Tanuja  Pant  Vimlesh  Chandra  Navin 《Natural Hazards》2021,106(3):1981-2001
Natural Hazards - Oceanic eddies span over a wide range of sizes and affect the thermodynamic properties of water column. By modifying the thermal structure of the upper ocean, these eddies...  相似文献   
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