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Natural Resources Research - Geological contacts in lateritic metal deposits (footwall topographies) often delineate the orebody boundaries. Spatial variations seen in such contacts are frequently...  相似文献   
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Zulfiqar  Farah  Shang  Jie  Zada  Muhammad  Alam  Qamar  Rauf  Tariq 《GeoJournal》2021,86(6):2767-2776

Based on the survey data of 250 farmers from the Multan district of Southern region of Punjab, Pakistan this study aims to empirically examine the determinants of access to agricultural credit. This study used the probit model to analyze the data. The results revealed that formal education, farm size, level of farm mechanization, farm revenue and landholding size positively and significantly influenced access to agricultural credit while the age of the farmer’s, distance, and off- farm income negatively and insignificantly influenced farmer’s accessibility to agricultural credit. The findings of the current study offer a policy guideline to streamline national policy on agricultural finance. This study also recommends that ZaraiTaraqiati Bank (ZTBL) and other Commercial Banks should improve their agricultural credit schemes to fulfil the diversified needs of small farm holders.

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A new instrument (LOPAP: LOng Path liquid Absorption Photometer) for the sensitive detection of nitric acid (HNO3) in the atmosphere is described. HNO3 is sampled in a temperature controlled stripping coil mounted in an external sampling module to minimize sampling artefacts in sampling lines. After conversion into a strongly absorbing dye, HNO3 is detected in long path absorption in special Teflon® AF 2400 tubes used as liquid core wave guides. For the correction of some interferences, due to for example HONO and particle nitrate, two channels are used in series. The interferences from several potential interfering compounds including particle nitrate were quantified in the laboratory and in a large outdoor simulation chamber. With the exception of the interference caused by N2O5, which is quantitatively measured by the instrument, all tested interferences can be corrected under atmospheric conditions. Thus, in the instrument only the sum of N(V) from HNO3 and N2O5 is determined, which is expected to be a common problem of wet chemical HNO3 instruments. The instrument has a detection limit of 5–30 pptv for a time response of 6–2 min, respectively and was validated against the FTIR technique in a large outdoor simulation chamber. In addition, the applicability of the instrument was demonstrated in a field campaign.  相似文献   
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Li  Zhenya  Ali  Zulfiqar  Cui  Tong  Qamar  Sadia  Ismail  Muhammad  Nazeer  Amna  Faisal  Muhammad 《Natural Hazards》2022,111(1):547-566
Natural Hazards - The increase of frequency and severity of extreme weather events due to climate change gives evidence of severe challenges faced by infrastructure systems. Among them, the...  相似文献   
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Two Cardium horizons from the topmost Azraq Formation in the eastern desert of Jordan were investigated and dated by U/Th at 330 ka; MIS 9. Fossil diversity and abundance, especially for Charophytes and gastropods with the absence of palygorskite, dolomite and evaporites, suggest the presence of a fresh water lake changing to a brackish environment at certain time intervals. A lake or possibly several smaller and shallower lakes occupied an area of about 50 km wide within the Azraq Basin. The present-day arid climate cannot support the presence of lakes in the eastern desert of Jordan, and thus MIS 9 in Jordan must have been much wetter. The source of humidity was most probably more intense Mediterranean cyclones associated with warmer than present MIS 9. However, the possibility of summer monsoon rain from the south cannot be fully excluded.  相似文献   
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An early warning system forewarns an urban area of the forthcoming strong shaking, normally with a few seconds to a few tens of seconds of early warning time before the arrival of the destructive S-wave part of the strong ground motion. For urban and industrial areas susceptible to earthquake damage, where the fault rupture system is complex and the fault-site distances are short, there is usually insufficient time to compute the hypocenter, focal parameters and the magnitude of an earthquake. Therefore, simpler and robust early warning algorithm is needed. The direct (engineering) early warning systems are based on algorithms of the exceedance of specified threshold time domain amplitude levels. The continuous stations’ data are processed to compute specific engineering parameters robustly and compared with specified threshold levels. The parameters can be chosen as band-pass filtered peak ground accelerations and/or the bracketed cumulative absolute velocity (BCAV). In this paper, an enhancement to bracket cumulative absolute velocity for the application of online urban early warning systems results in a new parameter called window based bracketed cumulative absolute velocity (BCAV-W). The BCAV-W allows computation of cumulative absolute velocity in a specified window size and to include the vertical component of the motion. The importance of choosing optimum window size for the cumulative absolute velocity BCAV-W is discussed and the correlations between BCAV-W and the macro-seismic intensity are studied for three combinations of horizontal and vertical components of the motion. Empirical relationship is developed to estimate BCAV-W as a function of magnitude, distance, fault mechanism, and site category based on 1,208 recorded ground motion data from 75 earthquakes in active plate-margins.  相似文献   
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