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161.
162.
1INTRODUCTION NepentheswhichareknownlocallyinPeninsular Malaysiaasperiukkerabelongtoamonogenericfami lyNepenthaceae.Atpresent,atotalofninespecies(excludingnaturalhybrids)arerecordedfromPenin sularMalaysia.Ofthese,fourspeciesareendemic,whilsttheotherfivespeciesarefoundoutsidethepen insula.Thespeciescanarbitrarilybeclassifiedinto thelowlandspeciesandthehighlandspecies(Clarke,2002;Shivas,1984;Kurata,1976).Threespeciesarefoundinthehighlandhabitatscom monlyatanelevationofabove1000mforaboves…  相似文献   
163.
ABSTRACT

Large porphyry Cu-Au deposits are associated with Early Miocene intrusive rocks in Tethyan belt, discovered along Chagai magmatic arc in Western Pakistan, adjacent to Southeast Iran. Two types of rocks were discriminated as granodiorite and monzodiorite from Saindak area. The granodiorites are associated with regional large Cu-Au mineralization, while the monzodiorites are mostly ore-barren. LA-ICP-MS U-Pb dating yielded weighted mean 206Pb/238U ages of 22.16–24.2 Ma for granodiorites and ca. 22.6 Ma for a monzodiorite. These intrusive rocks in the Saindak area are all calc-alkaline rocks, with enriched LILEs and depleted HFSEs, and without Eu negative anomalies. The felsic granodiorites are characterized by high Sr contents and Sr/Y ratios, with intermediate to high (La/Yb)N ratios that identify them as typical high-silica adakites. In contrast, the basaltic-andesitic monzodiorites are just normal arc-related rocks, showing less fractionated REE patterns than the granodiorites, with systematically lower LREE and higher MREE and HREE. Low K2O/Na2O ratios and decoupled Sr/Y-(La/Yb)N ratios indicate the characteristics of slab-derived adakites for the granodiorites, most likely originated through partial melting of the subducted Neotethys oceanic crust beneath Eurasian continent followed by subsequent mantle interaction. The almost simultaneously melting of subcontinental lithospheric mantle induced by dehydration of Neotethys plate gave rise to the formation of the barren monzodiorites. These intrusive rocks in the Saindak area are characterized by similar Sr-Nd-Pb isotopes with high 87Sr/86Sri ratios, slightly negative εNd(t) values and radiogenic Pb isotopes, plotting in the field between the MORB and EM-II mantle endmembers or the Average Cadomian Lower Crust, suggesting subducting sediments or old continental crustal materials have contributed into the compositions of these rocks by source enrichment or crustal contamination. The slab-melting derived adakite is favourable for regional massive Cu-Au mineralization in the Saindak area.  相似文献   
164.
A Greek oil-tanker ran aground, resulting in a huge oil spill along the costal areas of Karachi, Pakistan. The purpose of this study was to assess the lung function and follow up change after one year in subjects exposed to crude oil spill in sea water. It was a cross sectional study with follow up in 20 apparently healthy, non-smoking, male workers, who were exposed to a crude oil spill environment during oil cleaning operation. The exposed group was matched with 31 apparently healthy male control subjects. Pulmonary function test was performed using an electronic Spirometer. Subjects exposed to polluted air have significant reduction in forced vital capacity (FVC), forced expiratory volume in first second (FEV(1)), forced expiratory flow (FEF(25-75%)) and maximum voluntary ventilation (MVV) compared to their matched controls. This impairment was reversible and lung functions parameters were improved when the subjects were withdrawn from the polluted air environment.  相似文献   
165.
The aim of this study is to assess the performance of linear discriminate analysis, support vector machines (SVMs) with linear and radial basis, classification and regression trees and random forest (RF) in the classification of radionuclide data obtained from three different types of rocks. Radionuclide data were obtained for metamorphic, sedimentary and igneous rocks using gamma spectroscopic method. A P-type high-purity germanium detector was used for the radiometric study. For analysis purpose, we have determined activity concentrations of 232Th, 226Ra and 40K radionuclides, published elsewhere (Rafique et al. in Russ Geol Geophys 55:1073–1082, 2014), in different rock samples and built the classification model after pre-processing the data using three times tenfold cross-validation. Using this model, we have classified the new samples into known categories of sedimentary, igneous and metamorphic. The statistics depicts that RF and SVM with radial kernel outperform as compared to other classification methods in terms of error rate, area under the curve and with respect to other performance measures.  相似文献   
166.
The Industrialized Building System (IBS) was recently introduced to minimize the time and cost of project construction. Accordingly, ensuring the integration of the connection of precast components in IBS structures is an important factor that ensures stability of buildings subjected to dynamic loads from earthquakes, vehicles, and machineries. However, structural engineers still lack knowledge on the proper connection and detailed joints of IBS structure construction. Therefore, this study proposes a special precast concrete wall-to-wall connection system for dynamic loads that resists multidirectional imposed loads and reduces vibration effects (PI2014701723). This system is designed to connect two adjacent precast wall panels by using two steel U-shaped channels (i.e., male and female joints). During casting, each joint is adapted for incorporation into a respective wall panel after considering the following conditions: one side of the steel channel opens into the thickness face of the panel; a U-shaped rubber is implemented between the two channels to dissipate the vibration effect; and bolts and nuts are used to create an extension between the two U-shaped male and female steel channels. The developed finite element model of the precast wall is subjected to cyclic loads to evaluate the performance of the proposed connection during an imposed dynamic load. Connection performance is then compared with conventional connections based on the energy dissipation, stress, deformation, and concrete damage in the plastic range. The proposed precast connection is capable of exceeding the energy absorption of precast walls subjected to dynamic load, thereby improving its resistance behavior in all principal directions.  相似文献   
167.
In this article, we suggest a Sitter model in favor of compact stars in low-mass X-ray binaries.Here, we have considered the presence of a cosmological constant(on a small scale) to investigate the stellar structure. We conclude that this approach is very suitable for the familiar physical model of compact stars in low-mass X-ray binaries. We calculate the probable radius, compactness(u) and surface redshift(Z_s) of six compact stars in low-mass X-ray binaries, namely Cyg X-2, V395 Carinae/2 S 0921–630, XTE J2123–058,X1822–371(V691 CrA), 4 U 1820–30 and GR Mus(XB 1254–690). We also offer a possible equation of state(EOS) for the stellar objects.  相似文献   
168.
We examine the warm inflationary universe model in the presence of generalized cosmic Chaplygin gas and standard scalar field. We assume the generalized dissipative coefficient and corresponding weak and strong dissipative regimes. In this framework, we analyze the characteristics of inflationary dynamics under the slow-roll approximations. Under these approximations, we formulate the important inflationary parameters, such as scalar spectral index, scalar and tensor power spectrum, tensor-to-scalar ratio etc. It is interesting to note that our results for these inflationary parameters are well corroborated with the recent observational data like WMAP7, WMAP9 and Planck data.  相似文献   
169.
Within the framework of potential cluster model, astrophysical S-factor of radiative capture reaction \(^{12}\mathrm{C} (\mathrm{p},\gamma)^{13}\mathrm{N}\) has been calculated in the two body cluster model for the energy range 0–1 MeV. The nuclear interaction in the initial and final states is described by the Woods–Saxon potential. The calculated astrophysical S-factor and rates are compared with known experimental results.  相似文献   
170.
MXB 1658-298 is a transient Low-Mass X-ray Binary (LMXB), which shows eclipses, dips and bursts in its light curve. This source has undergone three active periods separated by long quiescent phases. The latest phase of enhanced X-ray emission was observed during 2015–2016. We have analysed broadband data from Swift/XRT and NuSTAR observations carried out in 2015. During NuSTAR observation, one thermonuclear X-ray burst took place. The X-ray emission during the burst was brighter by a factor of \(\sim 200\), compared to the pre-burst emission. This work focuses on the spectral analysis of MXB 1658-298 during the persistent and the burst phases using NuSTAR observation of 2015. We have also determined the temperature and radius evolution during the burst using the time-resolved spectroscopy. The burst phase shows mild Photospheric Radius Expansion (PRE).  相似文献   
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