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排序方式: 共有1311条查询结果,搜索用时 31 毫秒
111.
Saeed Karimi Nasab Azadeh Hojat Abolghasem Kamkar-Rouhani Hossein Akbari Javar Saeed Maknooni 《Mine Water and the Environment》2011,30(3):208-215
Geoelectrical surveys were conducted in Area 3 of the Gol-e-Gohar iron ore mine to provide geological and hydrogeological
information. Open pit mining is currently underway in the northern part of the Area, and underground mining operations are
planned for the southern section. Groundwater has already been encountered in the open pit mine. Twenty five resistivity soundings
were first performed in the mine area; then, induced polarization (IP) measurements were carried out to remove ambiguities
between clay and water-bearing layers. To investigate fault zones as water conduits, combined resistivity profiling surveys
were also carried out. These measurements provided a detailed structural map of the pit area. Resistivity and IP results have
subsequently been confirmed by observations at three monitoring wells and the mine pit wall. Monitoring and piezometric wells
will be drilled at locations suggested by the results of the geoelectrical surveys. Drainage galleries may be developed to
dewater the open pit mine. However, another option being considered is to start the underground mining with the idea that
it will initially simply serve as a dewatering mechanism. 相似文献
112.
Salman R. Salman 《Polymer-Plastics Technology and Engineering》2013,52(1-2):115-122
Photooxidative aging of high-impact polystyrene sheets at 25°C was followed for different intervals of 25, 40, 50, 75, and 80 h. Five different types of samples were used, viz. virgin, and recycled once, twice, three, and four times. The optical properties of exposed samples exhibited changes as a result of discoloration. The transmittance and reflection deceases whereas absorbance increases with increasing recycling of high-impact polystyrene. 相似文献
113.
Adnan Khan Bushra Shal Ashraf Ullah Khan Rahim Ullah Muhammad Waleed Baig Ihsan ul Haq Eun Kyoung Seo Salman Khan 《International journal of molecular sciences》2021,22(11)
Vincristine (VCR) is a widely used chemotherapy drug that induced peripheral painful neuropathy. Yet, it still lacks an ideal therapeutic strategy. The transient receptor potential (TRP) channels, purinergic receptor (P2Y), and mitogen-activated protein kinase (MAPK) signaling play a crucial role in the pathogenesis of neuropathic pain. Withametelin (WMT), a potential Phytosteroid isolated from datura innoxa, exhibits remarkable neuroprotective properties. The present investigation was designed to explore the effect of withametelin on VCR-induced neuropathic pain and its underlying molecular mechanism. Initially, the neuroprotective potential of WMT was confirmed against hydrogen peroxide (H2O2)-induced PC12 cells. To develop potential candidates for neuropathic pain treatment, a VCR-induced neuropathic pain model was established. Vincristine (75 μg/kg) was administered intraperitoneally (i.p.) for 10 consecutive days (day 1–10) for the induction of neuropathic pain. Gabapentin (GBP) (60 mg/kg, i.p.) and withametelin (0.1 and 1 mg/kg i.p.) treatments were given after the completion of VCR injection on the 11th day up to 21 days. The results revealed that WMT significantly reduced VCR-induced pain hypersensitivity, including mechanical allodynia, cold allodynia, and thermal hyperalgesia. It reversed the VCR-induced histopathological changes in the brain, spinal cord, and sciatic nerve. It inhibited VCR-induced changes in the biochemical composition of the myelin sheath of the sciatic nerve. It markedly downregulated the expression levels of TRPV1 (transient receptor potential vanilloid 1); TRPM8 (Transient receptor potential melastatin 8); and P2Y nociceptors and MAPKs signaling, including ERK (Extracellular Signal-Regulated Kinase), JNK (c-Jun N-terminal kinase), and p-38 in the spinal cord. It suppressed apoptosis by regulating Bax (Bcl2-associated X-protein), Bcl-2 (B-cell-lymphoma-2), and Caspase-3 expression. It considerably attenuated inflammatory cytokines, oxidative stress, and genotoxicity. This study suggests that WMT treatment suppressed vincristine-induced neuropathic pain by targeting the TRPV1/TRPM8/P2Y nociceptors and MAPK signaling. 相似文献
114.
King Eden B.; Dunleavy Dana G.; Dunleavy Eric M.; Jaffer Salman; Morgan Whitney Botsford; Elder Katie; Graebner Raluca 《Canadian Metallurgical Quarterly》2011,17(1):54
Although scholars agree that traditional forms of discrimination have generally been supplanted by subtler interpersonal manifestations of discrimination, it is yet unknown whether targets of these behaviors or the American judicial branch recognize such negative behaviors as violations of extant law. Extending research and theory, we propose that denigrating messages toward women and ethnic minorities (i.e., microaggressions) emerge in workplace interactions and are sometimes interpreted as discrimination. Specifically, this research explores the presence, severity, and frequency of microaggressions that appear in a random sample of race and gender discrimination cases in federal court dockets since the year 2000. The results suggest that microinsults, microinvalidations, and microassaults are reported in a variety of discrimination claims. However, only overt and intentional forms of microaggressions (microassaults) increased the likelihood that decisions favored plaintiffs. Thus, there may be a disconnect between forms of discrimination perceived by claimants and how those forms are evaluated by the legal system that protects victims of discrimination. This potential misalignment of science and practice is discussed, as are directions for future research. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
115.
Salman M. A. Salman 《国际水》2013,38(4):580-585
Abstract International rivers serve a number of purposes, the most obvious are the navigational and non-navigational uses. Less noticed is the fact that international rivers are also used to delimit boundaries between nations. The immediate question that would arise is: Where are such boundaries actually drawn across the river? Boundaries, however, are established by treaties and the answer to this question is often included in the interpretation of treaties delimiting such water boundaries, taking into account the special characteristics of the international river. Indeed, this has been the case regarding the boundaries across the Chobe river between Botswana and Namibia. Determining where such boundaries lie would result in deciding to whom a disputed Island, the Kasikili/Sedudu, belongs. In a praiseworthy step, the two countries agreed to take their dispute over the Island, after failure to resolve it through negotiations, to the International Court of Justice. This paper discusses the uses of international rivers as boundaries, and reviews the dispute between Botswana and Namibia, and the decision of the Court thereon. 相似文献
116.
This paper presents the finite element simulations of deformation and fracture of a gas cylinder which catastrophically failed as a result of an accidental explosion. The results of a previous detailed investigation of this incident indicated that detonation of a low-pressure oxygen-rich mixture of hydrogen and oxygen was the cause of the cylinder failure. In the current study, the finite element method was used to provide a more realistic modeling of geometry, material behavior, and boundary conditions of the cylinder. The overall transient dynamic response of the cylinder to gaseous detonation loading was studied using the ANSYS/LS-DYNA V10 package and the crack growth simulations were performed using the WARP3D-R15 research code. The crack growth analyses were performed using interface cohesive elements. The finite element results were validated using analytical solutions and data collected from the remains of the cylinder. The simulations clearly showed that the stresses caused by the assumed loading profile were indeed capable of creating local ruptures at the actual crack initiation sites. It was also shown that the self-similar growth of the initial axial crack in the main body of the cylinder was a fatigue-type incremental growth governed by the structural waves. The subsequent cyclic bulging of the crack flaps and the resultant crack curving and branching were also simulated. 相似文献
117.
The crystallization behaviour of lithia calcia silicate system containing MgO, SrO, and Al2O3 has been investigated using DTA, XRD and SEM. The coefficient of thermal expansion and Vicker's microhardness of the obtained products were also evaluated. The main crystalline phases formed after different heat-treatments were lithium metasilicate, wollastonite, diopside, β-spodumene ss, pseudo-wollastonite, Sr2SiO4, Sr2Mg(Si2O7) and μ-(Ca,Sr)SiO3. The wollastonite structure can accept considerable amount of strontium to form wollastonite strontium solid solution, while there is no solid solution of strontium in pseudo-wollastonite. 相似文献
118.
Seyyed Reza Pishva Ramachandran Vasudevan Ali Etemad Farzad Heidari Makanko Komara Patimah Ismail Fauziah Othman Abdollah Karimi Mohammad Reza Sabri 《International journal of molecular sciences》2013,14(2):2739-2752
Ventricular septal defect (VSD) is one of the most common types of congenital heart defects (CHD). There are vivid multifactorial causes for VSD in which both genetic and environmental risk factors are consequential in the development of CHD. Methionine synthase reductase (MTRR) and methylenetetrahydrofolate reductase (MTHFR) are two of the key regulatory enzymes involved in the metabolic pathway of homocysteine. Genes involved in homocysteine/folate metabolism may play an important role in CHDs. In this study; we determined the association of A66G and C524T polymorphisms of the MTRR gene and C677T polymorphism of the MTHFR gene in Iranian VSD subjects. A total of 123 children with VSDs and 125 healthy children were included in this study. Genomic DNA was extracted from the buccal cells of all the subjects. The restriction fragment length polymorphism polymerase chain reaction (PCR-RFLP) method was carried out to amplify the A66G and C524T polymorphism of MTRR and C677T polymorphism of MTHFR genes digested with Hinf1, Xho1 and Nde1 enzymes, respectively. The genotype frequencies of CC, CT and TT of MTRR gene among the studied cases were 43.1%, 40.7% and 16.3%, respectively, compared to 52.8%, 43.2% and 4.0%, respectively among the controls. For the MTRR A66G gene polymorphism, the genotypes frequencies of AA, AG and GG among the cases were 33.3%, 43.9% and 22.8%, respectively, while the frequencies were 49.6%, 42.4% and 8.0%, respectively, among control subjects. The frequencies for CC and CT genotypes of the MTHFR gene were 51.2% and 48.8%, respectively, in VSD patients compared to 56.8% and 43.2% respectively, in control subjects. Apart from MTHFR C677T polymorphism, significant differences were noticed (p < 0.05) in C524T and A66G polymorphisms of the MTRR gene between cases and control subjects. 相似文献
119.
A Comparison Between Cold-Welded and Diffusion-Bonded Al/Cu Bimetallic Rods Produced by ECAE Process
P. Eslami A. Karimi Taheri M. Zebardast 《Journal of Materials Engineering and Performance》2013,22(10):3014-3023
In this research, the application of equal channel angular extrusion process to produce both the cold-welded and diffusion-bonded Al/Cu bimetallic rods is assessed. The joints shear strength for both of the methods are measured and compared. The microstructure examinations were also carried out using scanning electron microscope equipped with EDX system and x-ray diffraction analysis. The results exhibit that the strength of the bond in cold-welded specimens is dependent on the amount of stretch and pressure at the materials interface. But in the diffusion-bonded specimens, it is depended on the struggle between the oxidation rate of the mating surfaces accompanied by inter-metallic compounds formation and the aluminum and copper atoms ability to diffuse in the joint interface. 相似文献
120.
Salman M.A. Salman 《国际水》2013,38(3):415-418
Abstract Of the voluminous resolutions issued by United Nations General Assembly, the Millennium Declaration, adopted in 2000, is one of the most significant. It specifies eight development goals and sets the year 2015 as the target date for achieving such goals. Although water is not explicitly mentioned as one of those eight principal goals, it is specified as a subset under one of those goals. Three years later, the United Nations General Assembly paid special attention to water by issuing a separate resolution declaring the period 2005 to 2015 as the “International Decade for Action, Water for Life.” This article reviews and discusses the Resolution and analyzes its added value. 相似文献