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21.
22.
A series of nanocrystalline Li0.25Ni0.5Fe2.25−xErxO4 (x=0.00, 0.02, 0.06, 0.08, and 0.10) ferrite powders, having a cubic spinel crystal structure and a low value of coercivity, was synthesized by the sol–gel auto-combustion route. The structure, morphology and magnetic properties of the prepared nanoferrites were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and the magnetic property measurement system (MPMS). A well-defined single phase spinel structure is confirmed in all the samples by X-ray diffraction analysis. The lattice parameters of the samples increase slightly with increasing the erbium content. The crystallite size of the Er-doped samples is smaller than that of pure Li–Ni ferrite, and decrease regularly in the range of 36.0–14.5 nm. It has been observed that the magnetic properties of these ferrites are strongly influenced by the added erbium content. The magnetic measurements indicate that saturation magnetization (Ms) and coercivity (Hc) decrease gradually with the increase of Er content in the lattice. 相似文献
23.
Rabia Rasool Inam Ullah Bismillah Mubeen Sultan Alshehri Syed Sarim Imam Mohammed M. Ghoneim Sami I. Alzarea Fahad A. Al-Abbasi Bibi Nazia Murtaza Imran Kazmi Muhammad Shahid Nadeem 《International journal of molecular sciences》2022,23(3)
Breast cancer is a diverse disease caused by mutations in multiple genes accompanying epigenetic aberrations of hazardous genes and protein pathways, which distress tumor-suppressor genes and the expression of oncogenes. Alteration in any of the several physiological mechanisms such as cell cycle checkpoints, DNA repair machinery, mitotic checkpoints, and telomere maintenance results in genomic instability. Theranostic has the potential to foretell and estimate therapy response, contributing a valuable opportunity to modify the ongoing treatments and has developed new treatment strategies in a personalized manner. “Omics” technologies play a key role while studying genomic instability in breast cancer, and broadly include various aspects of proteomics, genomics, metabolomics, and tumor grading. Certain computational techniques have been designed to facilitate the early diagnosis of cancer and predict disease-specific therapies, which can produce many effective results. Several diverse tools are used to investigate genomic instability and underlying mechanisms. The current review aimed to explore the genomic landscape, tumor heterogeneity, and possible mechanisms of genomic instability involved in initiating breast cancer. We also discuss the implications of computational biology regarding mutational and pathway analyses, identification of prognostic markers, and the development of strategies for precision medicine. We also review different technologies required for the investigation of genomic instability in breast cancer cells, including recent therapeutic and preventive advances in breast cancer. 相似文献
24.
Yasir Ul Haq Imran Murtaza Sadaf Mazhar Naeem Ahmad Awais A. Qarni Zeeshan Ul Haq Shahid A. Khan Mahmood Iqbal 《应用聚合物科学杂志》2020,137(40):49197
Electric power system applications demand for high-temperature dielectric materials. The improved performance of polymer nanocomposites requires improvement in their thermal conductivity & stability, dielectric stability and processing technique. However, they often lose their dielectric properties with a rise in temperature. Here, we offer a solution by incorporating electrically conducting material (MXene) and semiconducting inorganic nanoparticles (ZnO NPs) into an insulating PMMA polymer matrix to maintain high dielectric constant, both at the room and high temperature. Therefore, to achieve desirable thermal and dielectric properties is the main objective of the present study based on the homogeneous distribution of the nanofillers by in-situ bulk polymerization assisted by strong sonication in the corresponding polymer. The introduction of MXene and ZnO NPs into the PMMA not only acquires a substantial increment in the dielectric constant, to attain a value 437, with minimum energy loss of 0.36 at 25 Hz, but also improves the thermal conductivity of PMMA up to 14 times by causing the reduction of thermal resistance, which is actually responsible for the poor thermal conductivity of amorphous pure PMMA polymer. More importantly, hybrid PMMA/4:2 wt% MXene:ZnO nanocomposite leads to an excellent thermal stability. Moreover, further characterization of the synthesized nanocomposites by FTIR, SEM and XRD leads to the evaluation of strong interaction of ternary components with PMMA matrix. 相似文献
25.
The potentials of silty clay(SC), acquired from Chaman, Balochistan, were investigated as adsorbent for Ni(Ⅱ)and Cd(Ⅱ) removal from contaminated media. The influence of different operating factors like dose, pH, temperature, and time of contact was explored, and optimum values were noted under batch adsorption method. Isothermal study was conducted with varying concentrations of solutions on optimized conditions and different adsorption models i.e., Langmuir, Freundlich, Temkin and Dubinin–Radushkevich(D–R) isotherm, which were employed to interpret the process. The isothermal data of both Ni(Ⅱ) and Cd(Ⅱ) were well fitted to Langmuir isotherm suggesting the formation of monolayer of metal ions on silty clay. The values of adsorption capacity noted for Ni(Ⅱ) and Cd(Ⅱ) were 3.603 mg·g~(-1) and 5.480 mg·g~(-)1, respectively. Kinetic studies affirmed that pseudo second order(PSO) kinetics was being obeyed by the removal of Ni(Ⅱ) and Cd(Ⅱ). Thermodynamic variables like free energy change(ΔG°), enthalpy change(ΔH°) and entropy change(ΔS°) were calculated. The negative value of ΔG° and the positive values of ΔH° and ΔS° unfolded that the removal process of both metal ions of by SC was spontaneous, endothermic and feasible. 相似文献
26.
Aqib Muzaffar Kalim Deshmukh S. K. Khadheer Pasha 《Polymer-Plastics Technology and Engineering》2020,59(15):1667-1678
ABSTRACT Polyvinylchloride (PVC)/nickel oxide (NiO)/tungsten oxide (WO3) nanocomposite films were prepared via solution casting technique. The crystallinity, morphology, and the analysis of dispersion state of PVC/NiO/WO3 nanocomposite was carried out using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The dielectric studies of nanocomposite films were investigated and a maximum dielectric constant of 2.3 with dielectric loss (tan δ) of 2.4 was attained. The EMI shielding studies were carried out in the X and Ku-band frequency range (8 GHz-18 GHz). The maximum SE of 15.78 dB in X-band and 12.05 dB in Ku-band was achieved for 75/20/5 compositions of the PVC/NiO/WO3 nanocomposite. 相似文献
27.
Sabiha Sultana Haq Nawaz Bhatti Farah Yasmin Abdul Naeem Khan Imran Rehan Kamran Rehan Noor-ul-Amin 《应用聚合物科学杂志》2020,137(7):48376
In the current study, graphene oxide (GO) was prepared using green chemistry with modified Hummer's method without incorporating sodium nitrate (NaNO3). Solvent casting was employed to fabricate GO-doped poly(ethylene oxide) (PEO), that is, PEO/GO composites with various proportion of Na2SO4 and were then subjected to characterization via advanced spectroscopic techniques for different physicochemical aspects to estimate their potential applications as marketable products. XRD analysis explored that fabricated composites are more crystalline than neat PEO. PEO/GO/Na2SO4 composite films offered maximum crystallinity. SEM displayed the same trend. TG/DTA thermogram exposed better thermal stability than pristine polymer. FTIR studies confirmed complexation among hybrid's components. Elongation-at-break and Young's modulus displayed an enhancing behavior with an incremental loading of salt and filler. In terms of mechanical performance, composite of PEO with 0.37 wt % GO and 0.08 g salt was found to be an ideal composition during the course of study. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48376. 相似文献
28.
Uzma Arif Nawaz M. Rana Shafia Qureshi Imran Haider Elmasry Yasser Hussain Shafiq 《Theoretical Foundations of Chemical Engineering》2020,54(6):1327-1339
Theoretical Foundations of Chemical Engineering - In this study, the simulations for first-order chemical reactions (constructive and destructive) in the flow of the Casson fluid with... 相似文献
29.
Synthesis of Sulfur‐Based Biocompatible Nonionic Surfactants and Their Nano‐Vesicle Drug Delivery 下载免费PDF全文
Imdad Ali Muhammad Raza Shah Muhammad Imran Shafiullah 《Journal of surfactants and detergents》2017,20(6):1367-1375
Nonionic surfactants are capable of forming nano‐range vesicles upon self‐assembling in an aqueous medium. These vesicles are highly stable, low in toxicity, and cost‐effective. Owing to their ability to solubilize both hydrophilic and hydrophobic substances, they are of great interest for drug solubilization and delivery. This study describes the synthesis and characterization of two new nonionic surfactants and their screening for biocompatibility and drug loading potentials in nano‐scale niosomal vesicles. They were characterized through mass spectroscopy, 1HNMR, and FT‐IR. Their critical micelle concentration (CMC) was investigated using UV–vis spectrophotometry. The biocompatibility study was carried out through blood hemolysis and in vitro cytotoxicity assays. The surfactants have very low CMC values, are highly hemo‐compatible, and were nontoxic when tested against a cell culture. They were able to form nano‐range niosomal vesicles with large variation in their size. Both new surfactants were able to encapsulate increased amounts of the drug, in this case clarithromycin. The chemical nature of the drug remained intact in the niosomal vesicles. The results suggest that these nonionic surfactants could be promising drug delivery vehicles. 相似文献
30.
Martina Casarin Tiago Moderno Fortunato Saima Imran Martina Todesco Deborah Sandrin Giulia Borile Ilaria Toniolo Massimo Marchesan Gino Gerosa Andrea Bagno Filippo Romanato Emanuele Luigi Carniel Alessandro Morlacco Fabrizio Dal Moro 《International journal of molecular sciences》2022,23(5)
Bladder cancer (BC) is among the most common malignancies in the world and a relevant cause of cancer mortality. BC is one of the most frequent causes for bladder removal through radical cystectomy, the gold-standard treatment for localized muscle-invasive and some cases of high-risk, non-muscle-invasive bladder cancer. In order to restore urinary functionality, an autologous intestinal segment has to be used to create a urinary diversion. However, several complications are associated with bowel-tract removal, affecting patients’ quality of life. The present study project aims to develop a bio-engineered material to simplify this surgical procedure, avoiding related surgical complications and improving patients’ quality of life. The main novelty of such a therapeutic approach is the decellularization of a porcine small intestinal submucosa (SIS) conduit to replace the autologous intestinal segment currently used as urinary diversion after radical cystectomy, while avoiding an immune rejection. Here, we performed a preliminary evaluation of this acellular product by developing a novel decellularization process based on an environmentally friendly, mild detergent, i.e., Tergitol, to replace the recently declared toxic Triton X-100. Treatment efficacy was evaluated through histology, DNA, hydroxyproline and elastin quantification, mechanical and insufflation tests, two-photon microscopy, FTIR analysis, and cytocompatibility tests. The optimized decellularization protocol is effective in removing cells, including DNA content, from the porcine SIS, while preserving the integrity of the extracellular matrix despite an increase in stiffness. An effective sterilization protocol was found, and cytocompatibility of treated SIS was demonstrated from day 1 to day 7, during which human fibroblasts were able to increase in number and strongly organize along tissue fibres. Taken together, this in vitro study suggests that SIS is a suitable candidate for use in urinary diversions in place of autologous intestinal segments, considering the optimal results of decellularization and cell proliferation. Further efforts should be undertaken in order to improve SIS conduit patency and impermeability to realize a future viable substitute. 相似文献