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101.
Liu  Yang  Cai  Jianchao  Sahimi  Muhammad  Qin  Chaozhong 《Transport in Porous Media》2020,133(2):313-332
Transport in Porous Media - During waterflooding, spontaneous imbibition is a fundamental recovery mechanism in fractured reservoirs. A large number of numerical and experimental studies have been...  相似文献   
102.
Faisal  Muhammad  Saeed  Aamer  Shahzad  Danish  Dar  Parsa  Larik  Fayaz Ali 《Molecular diversity》2020,24(2):571-592
Molecular Diversity - Aldehydes and ketones are parts of millions of compounds and are important classes of chemicals which serve as important precursors for the synthesis of library of compounds....  相似文献   
103.
Ferroptosis is a recently described programmed cell death mechanism that is characterized by the buildup of iron (Fe)-dependent lipid peroxides in cells and is morphologically, biochemically, and genetically distinct from other forms of cell death, having emerged to play an important role in cancer biology. Ferroptosis has significant importance during cancer treatment because of the combination of factors, including suppression of the glutathione peroxidase 4 (Gpx4), cysteine deficiency, and arachidonoyl (AA) peroxidation, which cause cells to undergo ferroptosis. However, the physiological significance of ferroptosis throughout development is still not fully understood. This current review is focused on the factors and molecular mechanisms with the diagrammatic illustrations of ferroptosis that have a role in the initiation and sensitivity of ferroptosis in various malignancies. This knowledge will open a new road for research in oncology and cancer management.  相似文献   
104.
105.
In this work, we performed an analysis on the surface properties of polyethersulfone (PES)‐based ultrafiltration membranes that were prepared by incorporating acid functionalized multiwalled carbon nanotube (f‐MWCNT) and polyvinylpyrrolidone into membrane matrix via simple blending method. The bonding‐chemistry of the nanocomposites implanted within the PES membrane was investigated by Fourier transform infrared spectrometer while atomic force microscope was employed to observe the distribution of f‐MWCNT in the membrane matrix and further measured its agglomeration quantitatively. The resultant 3D atomic force microscope images provided the most satisfactory way to examine the distribution of nanomaterials in the membranes, and with the help of ‘point profile data’ the maximum height and width of the agglomerated cluster could be quantitatively calculated. Moreover, the surface profile studies of the membrane surface provided the information about the length, volume, area, perimeter, radius and diameter of grains. It was observed that PES/nanocomposite blended membranes were held together via strong hydrogen bonding, but poor dispersion of MWCNT in the membrane matrix reduced the membrane performance in terms of protein (pepsin and bovine albumin serum) rejection and increased the surface roughness. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
106.
Marine drugs are abundant in number, comprise of a diverse range of structures with corresponding mechanisms of action, and hold promise for the discovery of new and better treatment approaches for the management of several chronic diseases. There are huge reserves of natural marine biological compounds, as 70 percent of the Earth is covered with oceans, indicating a diversity of chemical entities on the planet. The marine ecosystems are a rich source of bioactive products and have been explored for lead drug molecules that have proven to be novel therapeutic targets. Over the last 70 years, many structurally diverse drug products and their secondary metabolites have been isolated from marine sources. The drugs obtained from marine sources have displayed an exceptional potential in the management of a wide array of diseases, ranging from acute to chronic conditions. A beneficial role of marine drugs in human health has been recently proposed. The current review highlights various marine drugs and their compounds and role in the management of chronic diseases such as cancer, diabetes, neurodegenerative diseases, and cardiovascular disorders, which has led to the development of new drug treatment approaches.  相似文献   
107.
Over the last several years, the number of concepts and technologies enabling the production of environmentally friendly products (including materials, consumables, and services) has expanded. One of these ways is cradle-to-cradle (C2C) certifiedTM. Life cycle assessment (LCA) technique is used to highlight the advantages of C2C and recycling as a method for reducing plastic pollution and fossil depletion by indicating the research limitations and gaps from an environmental perspective. Also, it estimates the resources requirements and focuses on sound products and processes. The C2C life cycle measurements for petroleum-based poly (ethylene terephthalate) (PET) bottles, with an emphasis on different end-of-life options for recycling, were taken for mainland China, in brief. It is considered that the product is manufactured through the extraction of crude oil into ethylene glycol and terephthalic acid. The CML analysis method was used in the LCIA for the selected midpoint impact categories. LCA of the product has shown a drastic aftermath in terms of environmental impacts and energy use. But the estimation of these consequences is always dependent on the system and boundary conditions that were evaluated throughout the study. The impacts that burden the environment are with the extraction of raw material, resin, and final product production. Minor influences occurred due to the waste recycling process. This suggests that waste degradation is the key process to reduce the environmental impacts of the production systems. Lowering a product’s environmental impact can be accomplished in a number of ways, including reducing the amount of materials used or choosing materials with a minimal environmental impact during manufacture processes.  相似文献   
108.
Medical image fusion (MIF) has received painstaking attention due to its diverse medical applications in response to accurately diagnosing clinical images. Numerous MIF methods have been proposed to date, but the fused image suffers from poor contrast, non-uniform illumination, noise presence, and improper fusion strategies, resulting in an inadequate sparse representation of significant features. This paper proposes the morphological preprocessing method to address the non-uniform illumination and noise by the bottom-hat–top-hat strategy. Then, grey-principal component analysis (grey-PCA) is used to transform RGB images into gray images that can preserve detailed features. After that, the local shift-invariant shearlet transform (LSIST) method decomposes the images into the low-pass (LP) and high-pass (HP) sub-bands, efficiently restoring all significant characteristics in various scales and directions. The HP sub-bands are fed to two branches of the Siamese convolutional neural network (CNN) by process of feature detection, initial segmentation, and consistency verification to effectively capture smooth edges, and textures. While the LP sub-bands are fused by employing local energy fusion using the averaging and selection mode to restore the energy information. The proposed method is validated by subjective and objective quality assessments. The subjective evaluation is conducted by a user case study in which twelve field specialists verified the superiority of the proposed method based on precise details, image contrast, noise in the fused image, and no loss of information. The supremacy of the proposed method is further justified by obtaining 0.6836 to 0.8794, 0.5234 to 0.6710, and 3.8501 to 8.7937 gain for QFAB, CRR, and AG and noise reduction from 0.3397 to 0.1209 over other methods for objective parameters.  相似文献   
109.
Composite materials and their applications constitute a hot field of research nowadays due to the fact that they comprise a combination of the unique properties of each component of which they consist. Very often, they exhibit better performance and properties compared to their combined building blocks. Graphene oxide (GO), as the most widely used derivative of graphene, has attracted widespread attention because of its excellent properties. Abundant oxygen-containing functional groups on GO can provide various reactive sites for chemical modification or functionalization of GO, which in turn can be used to develop novel GO-based composites. This review outlines the most recent advances in the field of novel dyes and pigments encompassing GO as a key ingredient or as an important cofactor. The interactions of graphene with other materials/compounds are highlighted. The special structure and unique properties of GO have a great effect on the performance of fabricated hybrid dyes and pigments by enhancing the color performance of dyes, the anticorrosion properties of pigments, the viscosity and rheology of inks, etc., which further expands the applications of dyes and pigments in dyeing, optical elements, solar-thermal energy storage, sensing, coatings, and microelectronics devices. Finally, challenges in the current development as well as the future prospects of GO-based dyes and pigments are also discussed. This review provides a reference for the further exploration of novel dyes and pigments.  相似文献   
110.
In this paper, closed-form mathematical expressions are obtained for the amplitudes of the harmonic and intermodulation products of the fiber optic Mach–Zehnder microphone excited by a multitone acoustical perturbation. The results show the strong dependence of the harmonic and intermodulation performance on the amplitude of the acoustical perturbation tones and the phase shift produced by the DC bias voltage applied to the reference fiber of the Mach–Zehnder interferometer. The results also show that depending on the phase shift produced by the DC bias voltage, either the third-order or the second-order intermodulation will be dominant. Compared to previously published results for other types of microphones, it appears that the phase shift produced by the DC bias voltage plays an important role in deciding the order of the dominant intermodulation product.  相似文献   
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