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91.
We shall introduce the notion of uniformly classical primary submodule that generalizes the concept of uniformly primary ideal as given by J. A. Cox and A. J. Hetzel. We also advance the companion concepts of fully uniformly classical primary module and uniformly primary compatible module. Along these lines, we present a characterization of Noetherian rings R for which every R-module is fully uniformly classical primary and we present a characterization of rings R for which every finitely generated R-module is uniformly primary compatible. Results illustrating connections among the notions of uniformly classical primary submodule, uniformly primary ideal, and uniformly primary submodule as given by R. Ebrahimi-Atani and S. Ebrahimi-Atani are also provided. 相似文献
92.
S. Mahmood N. Akhtar 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2008,49(2):217-222
Linear and nonlinear ion acoustic waves in the presence of adiabatically heated ions in magnetized electron-positron-ion plasmas
are studied. The Sagdeev potential approach is employed to obtain the energy integral equation in such a mulitcomponent plasma
using fluid theory. It is found that electron density humps are formed in the subsonic region in magnetized electron-positron-ion
plasmas. The amplitude of electron density hump is decreased with the increase of hot ion temperature in electron-positron-ion
plasmas. However, the increase in positron concentration and obliqueness of the wave increases the amplitude of nonlinear
structure. The increase in positron concentration also reduces the width of the nonlinear structure in a magnetized multicomponent
plasma. The numerical solutions in the form of solitary pulses are also presented for different plasma cases. The results
may be applicable to astrophysical plasma situations, where magnetized electron-positron-ion plasma with hot ions can exist. 相似文献
93.
α–Fe2O3/TiO2 Composite powders have been prepared by high energy ball-milling for different times. The composites were studied using Mössbauer Spectroscopy (MS) and X-ray diffraction (XRD). The patterns of XRD show broadening in the diffraction peaks, indicating a decrease in the particle size of the composites with milling time. Also, the XRD patterns show an evolving new structural phase correlated with an evolving Titanium ferrite species with milling time. Mössbauer Spectroscopy shows the evolving titanium ferrite species characterized by a quadrupole doublet at the expense of the α–Fe2O3 represented by the magnetic sextet. The doublet corresponding to the Ti-ferrite phase dominates the Mössbauer spectra at long milling time (greater than 100 h of milling). 相似文献
94.
In this paper we consider iteration of single-plateau functions, an important class of continuous functions with infinitely many forts, and investigate changes of number and length of plateaux under iteration.We use the indices flatness, plateau limit and limit length to formulate those changes. Furthermore, we compute the flatness, plateau limit and limit length for all the nine types of single-plateau functions. 相似文献
95.
Ghehsareh Hadi Roohani Zaghian Ali Zabetzadeh Sayyed Mahmood 《Nonlinear dynamics》2019,96(2):1191-1211
Nonlinear Dynamics - In this paper, a numerical simulation of an anomalous reaction–diffusion process in two-dimensional space with a nonlinear source term is presented. An efficient and... 相似文献
96.
Alireza Iranbakhsh Narges Oraghi Ardebili Zahra Oraghi Ardebili Mohammadreza Shafaati Mahmood Ghoranneviss 《Plasma Chemistry and Plasma Processing》2018,38(1):29-44
There is a huge interest in making and applying innovating functional devices based on basic sciences (like physics) to improve plant growth and resistance against various stress conditions. This research was carried out in order to investigate effects of cold plasma on expressions of heat shock factor A4A (HSFA4A), plant growth and post reactions to salt stress. Wheat seedlings were treated with plasma (0.84 W/cm2 surface power densities) at different exposure times. In both three and 6 h after plasma, inductions in expressions of HSFA4A were recorded in roots, compared to control. Six hours after treatments, plasma-induced the shoot expressions of HSFA4A in the treated seedlings, contrasted to 3 h. Plasma treatment caused not the only enhancement in shoot fresh and dry mass and total leaf area, but also alleviated adverse impacts of salinity. Destroying impacts of salinity on chlorophyll contents were mitigated by plasma. Peroxidase activity was decreased by 27% for salinity treatment alone over control, while it was increased by 15% for plasma and salinity-treated samples, compared to salinity control. The highest activities of phenylalanine ammonia lyase (PAL) were found in plasma treatment alone. PAL activity was found to be higher in plasma-pretreated seedlings counteracted to salt stress, relative to the salinity control. The plasma treatment may act as an effective elicitor to modify gene expression, thereby improving plant growth and resistance. Plasma technology should be considered as a new functional technology in plant sciences. 相似文献
97.
Shahrir Razey Sahamir Mohd Faizul Mohd Sabri Mohamand Syafie Mahmood Muhammad Akmal Bin Kamarudin Oussama Moutanabbir 《Liquid crystals》2018,45(4):522-535
The vibrational property of 2,3,6,7,10,11-hexakis(hexyloxy)triphenylene (HAT6) discotic liquid crystal (DLC) material is investigated in this research by using temperature-dependent Raman spectroscopy technique. One-dimensional (1D) charge transport mechanism in the DLC molecules is enabled in the columnar liquid crystalline (Dh) phase. The result indicates a high core-to-core correlation in the liquid crystal columnar phase, which has a ‘memory’ like effect that extends into isotropic phase at femtosecond timescale. This correlation is also confirmed through electrical conductivity measurement of DLCs, in which the electrical conductivity is enhanced in the DLC phase. DFT simulation was also carried out in order to elucidate the basic properties of HAT6 such as the band gap in the light of Raman spectra. An interesting outcome is that a freely unspecified boundary model produces in a more flexible molecule, resulting in a reduced band gap. Thus, this work provides an understanding of relationship between columnar order and electrical conductivity of HAT6 molecule, and potential strategy for design of DLCs in electronics application. 相似文献
98.
Ghazala Riaz Amtul Bari Tabinda Adeel Mahmood Mehvish Mumtaz Abdul Qadir 《Analytical letters》2018,51(8):1245-1263
The current study assessed the spatiotemporal variations and human health surveillance associated with organochlorine pesticide (OCP) contamination in water, sediments, and fish from Chenab River, Pakistan. The OCP determinations were performed using high-performance liquid chromatography with a reverse-phase C18 column. The total OCP levels ranged from 13.33 to 274.59?ng/L in water, 4.63 to 239.11?ng/g in sediments, and 23.79 to 387.12?ng/g in fish species. The overall pattern of mean OCP concentrations followed the order as ΣDDTs?>?Σendosulfan?>?aldrin and OCP pollution pattern among the headworks were Khanki Barrage?>?Qadirabad Barrage?>?Trimmu Barrage?>?Marala Barrage in all three environmental matrixes during both seasons. The estimated daily intake (EDI) for ∑OCPs was found to be 22.44?ng/kg/day. The hazard ratios calculated to assess the carcinogenic risk indicated that the values for ∑DDT and aldrin at the 95th percentile concentrations were greater than one, indicating the probability of carcinogenic risk occurrence of one in million populations due to fish consumption. Therefore, these high levels of OCPs and carcinogenic risk through fish consumption highlight the needs of immediate elimination of OCPs from riverine environment of Chenab River and we recommend long-term monitoring-based freshwater ecological studies to be conducted in the study area. 相似文献
99.
Abid Nazir Gill Areeba Iftikhar Ayoub Rashid Muhammad Amin Rana Rashad Mahmood Khan Hafiz M. Rafique Seemal Jelani Ahmad Adnan 《Journal of the Iranian Chemical Society》2018,15(9):1939-1945
The present study reports the green synthesis of starch–maleate (SM) at ambient temperature in solvent-free system using Rhizopus arrhizus lipase as a biocatalyst and maleic acid (MA) as an esterification agent. The synthetic scheme was found to be efficient, economical, and ecofriendly. The newly synthesized SM samples were characterized using Fourier transform infrared (FTIR) and proton nuclear magnetic resonance (1H NMR) spectroscopic techniques. The degree of substitution (DS) was found in the range of 0.53–0.62. Moreover, DS was found to be temperature and time-dependent. X-ray diffraction (XRD) exhibited that maleation did not change the crystalline nature of native starch. Scanning electron microscopy (SEM) revealed that size of SM granules was in the range of 4–18 µm. The activation energy (Ea) of SM formation was calculated to be 42.94 kcal mol?1 which clearly indicated the effective and rapid interaction of functional groups. Hence, the solvent-free solid-state synthetic methodology proved to be excellent for the synthesis of novel biomaterials with appreciable high DS for drug delivery and sorption of heavy metal ions from water. 相似文献
100.
Murtaza Hasan Ihsan Ullah Hina Zulfiqar Komal Naeem Arfa Iqbal Huma Gul Muhammad Ashfaq Nasir Mahmood 《Materials Today Chemistry》2018
Synthesis of nanomaterials is being gained extensive attention in the fields of chemistry, applied physics, catalysis, drug delivery and the most important in diagnosis and therapeutic applications. Recently, many reports have been published on physical and chemical synthesis of magnetic as well as metallic nanoparticles (NPs) with viable surface functionalization, but still there is a dire need of such strategies that can combine synthetic methodology with stable surface modification found in nature. Synthesis of NPs via biological methods is the possible way to solve these barriers. However, systematized summary and outlooks of NPs synthesis via biological entities with various influencing factors e.g. temperature, pH, concentration of reactants and reaction time has rarely been reported. This review will present the distinct advantages of biological synthesis of NPs over physical and chemical methods. It will also highlight the recent progress on synthesis of NPs via various biological systems i.e. plant, fungus, bacteria, and yeast. Furthermore, it will explain various factors that control the size, shape, and morphology of these NPs. Finally, it would present the future perspectives of green chemistry for the development of nano-science and -biotechnology. 相似文献