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41.
Vasanthapriya R. Neelakandeswari N. Uthayarani K. Chitra M. 《Journal of Inorganic and Organometallic Polymers and Materials》2021,31(11):4272-4280
Journal of Inorganic and Organometallic Polymers and Materials - This paper reports the performance of alizarin based SnO2 dye-sensitized solar cells. A novel template assisted method has been... 相似文献
42.
Tianxing Chen Tengteng Yao Hui Peng Andrew K. Whittaker Yao Li Shenmin Zhu Zhaoyang Wang 《Advanced functional materials》2021,31(45):2106079
The convenience of injectable hydrogels that can provide high loading of diverse phototherapy agents and further long-time retention at the tumor site has attracted tremendous interest in simultaneous photothermal and photodynamic cancer therapies. However, to incorporate the phototherapy agents into hydrogels, complex modifications are generally unavoidable. Moreover, these phototherapy agents usually suffer from low efficiency and work at different irradiation wavelengths outside the near infrared windows. Hence, a method for the fabrication of an injectable hydrogel for simultaneous photothermal therapy and photodynamic therapy, through the Schiff-base reaction between amido modified carbon dots (NCDs) and aldehyde modified cellulose nanocrystals is proposed. The NCDs act as both phototherapy agents and crosslinkers to form hydrogels. Significantly, the NCDs demonstrate an extremely high photothermal conversion efficiency of 77.6% which is among the highest levels for photothermal agents and a high singlet quantum yield of 0.37 under a single 660 nm light-emitting diode irradiation. The hydrogels are examined through in vitro and in vivo animal experiments which show nontoxic and effectively tumor inhibition. Thus, the strategy of direct reaction of phototherapy agents and the matrix not only provides new strategies for injectable hydrogel fabrication but paves a new road for advanced tumor treatment. 相似文献
43.
Multidimensional Systems and Signal Processing - In medical Image processing, the chief objective is to detect Neoplasm effectively. Neoplasm is basically a sort of abnormal excessive cell growth... 相似文献
44.
H. Alrobei M.K. Prashanth C.R. Manjunatha C.B. Pradeep Kumar C.P. Chitrabanu Prasanna D. Shivaramu K. Yogesh Kumar M.S. Raghu 《Ceramics International》2021,47(7):10322-10331
In the present study we made an effort to deploy eco-friendly synthesized reduced graphene oxide/Lanthanum Alluminate nanocomposites (RGO-LaAlO3) and Lanthanum Alluminate (LaAlO3) as adsorbents to remove dye from the synthetic media. XRD, SEM, BET surface area and EDX have been used to characterize the above-mentioned adsorbents. The impacts of different factors like adsorbent dosage, the concentration of adsorbate and PH on adsorption were studied. The best fit linear and nonlinear equations for the adsorption isotherms and kinetic models had been examined. The sum of the normalized errors and the coefficient of determination were used to determine the best fit model. The experimental data were more aptly fitted for nonlinear forms of isotherms and kinetic equations. Pseudo-second-order and Freundlich isotherm model fits the equilibrium data satisfactorily. Methyl orange (MO) has been used as model dye pollutant and maximum adsorption capacity was found to be 469.7 and 702.2 mg g?1 for LaAlO3 and RGO-LaAlO3, respectively. 相似文献
45.
Satya P. Moulik Animesh K. Rakshit Bappaditya Naskar 《Journal of surfactants and detergents》2021,24(6):535-549
Critical micelle concentration (CMC) is a fundamental physical parameter of surfactant aggregation in solution. The CMC is determined by different methods, tensiometry, conductometry, microcalorimetry, fluorimetry, and so on. However, it is known that though CMC is reported as a single value, in reality, micelle formation occurs over a narrow range of concentration for different experimental procedures produce different results. We shall discuss about a unique procedure of measuring correct CMC applicable to all potential methods used in practice. This is essential for the evaluation of thermodynamic properties of the micelle forming process in pure and mixed states in terms of solution theories. As we in this short documentary want to deal with various aspects of Milton Rosen's research—wherein we have also worked—a few other facets of surfactant chemistry research, besides the micelle formation, are also briefly discussed. In mixed surfactant systems, synergistic effects in various surfactant properties like detergency, foaming, solubilization, and so on are found whereas in some others non-synergistic effects are observed. Dehydration of micelles with an increase in temperature or by the addition of hydrophilic substances may cause clouding to the system. Soluble amphiphilic systems produce Gibbs monolayer at the air/water interface; insoluble amphiphiles form Langmuir monolayers. A documentary of the above aspects will be herein presented and discussed. We mention that this article is neither an original research article nor a review article. This is a mixture of the two: a documentary of both original research and some review of our works presented in memory of Prof. Milton Rosen. 相似文献
46.
This study describes the synthesis of ceramics, in which a micrometre-sized Al2O3–ZrO2 nanopowder was used as an oxide base for the hardening of the materials. To a suspension of this mixed metal oxide, the pore-forming crystallisation additives camphor and carbamide were added to produce ceramics with thin permeable pores. Camphor crystallised in the oxide suspension in the form of single pentagonal stars and сarbamide crystallised in the form of thin elongated needles. The use of the different crystallisation additives allowed the formation of ceramics after sintering that have both permeable and complex pore morphologies, where anisotropic properties were observed using carbamide as an additive but not when camphor was used. The total porosity of the resulting ceramics was 51.3%, with a compressive strength in the range of 17.3–92.3 MPa. 相似文献
47.
Manal A. Mahdy Sayed H. Kenawy Esmat M.A. Hamzawy Gehan T. El-Bassyouni I.K. El Zawawi 《Ceramics International》2021,47(9):12047-12055
The influence of adding 10, 20 and 30% molar ratio of silicon carbide (SiC) separately to a composite of wollastonite (W) with a fixed content of 10%Fe2O3 prepared by wet precipitation method was studied. The crystal structure of the annealed composite powders was inspected by X-ray diffraction (XRD); revealing multi-phase structure. The highest estimated crystallite size investigated by Scherrer equation of W, SiC, WFe:SiC10, WFe:SiC20 and WFe:SiC30 were 53.89, 54.6, 56.3, 48.5 and 54.6 nm respectively; demonstrating the formation of nanocomposites. Particles shape, size and crystallinity of the samples were studied using high resolution transmission electron microscope (HR-TEM). The band gap Eg values of the nanocomposites increased with SiC content having an intermediate value that lies between that of γ-Fe2O3 (maghemite) and SiC. Ferromagnetic and paramagnetic contributions were observed in the magnetic hysteresis loops for the composites. This study highlighted that the coercive field (Hci) of the composites improved with increasing the SiC content. The innovative wollastonite/Fe2O3/SiC with amended magnetic properties elicited attention due to their promising application in bone filler and industrial purposes. 相似文献
48.
Vlad F. Avram Imen Chamkha Eleonor sander-Frostner Johannes K. Ehinger Romulus Z. Timar Magnus J. Hansson Danina M. Muntean Eskil Elmr 《International journal of molecular sciences》2021,22(1)
Statins are the cornerstone of lipid-lowering therapy. Although generally well tolerated, statin-associated muscle symptoms (SAMS) represent the main reason for treatment discontinuation. Mitochondrial dysfunction of complex I has been implicated in the pathophysiology of SAMS. The present study proposed to assess the concentration-dependent ex vivo effects of three statins on mitochondrial respiration in viable human platelets and to investigate whether a cell-permeable prodrug of succinate (complex II substrate) can compensate for statin-induced mitochondrial dysfunction. Mitochondrial respiration was assessed by high-resolution respirometry in human platelets, acutely exposed to statins in the presence/absence of the prodrug NV118. Statins concentration-dependently inhibited mitochondrial respiration in both intact and permeabilized cells. Further, statins caused an increase in non-ATP generating oxygen consumption (uncoupling), severely limiting the OXPHOS coupling efficiency, a measure of the ATP generating capacity. Cerivastatin (commercially withdrawn due to muscle toxicity) displayed a similar inhibitory capacity compared with the widely prescribed and tolerable atorvastatin, but did not elicit direct complex I inhibition. NV118 increased succinate-supported mitochondrial oxygen consumption in atorvastatin/cerivastatin-exposed platelets leading to normalization of coupled (ATP generating) respiration. The results acquired in isolated human platelets were validated in a limited set of experiments using atorvastatin in HepG2 cells, reinforcing the generalizability of the findings. 相似文献
49.
Nikhil K. Tulsian Valerie Jia-En Sin Hwee-Ling Koh Ganesh S. Anand 《International journal of molecular sciences》2021,22(10)
Phosphodiesterases (PDEs) hydrolyze cyclic nucleotides to modulate multiple signaling events in cells. PDEs are recognized to actively associate with cyclic nucleotide receptors (protein kinases, PKs) in larger macromolecular assemblies referred to as signalosomes. Complexation of PDEs with PKs generates an expanded active site that enhances PDE activity. This facilitates signalosome-associated PDEs to preferentially catalyze active hydrolysis of cyclic nucleotides bound to PKs and aid in signal termination. PDEs are important drug targets, and current strategies for inhibitor discovery are based entirely on targeting conserved PDE catalytic domains. This often results in inhibitors with cross-reactivity amongst closely related PDEs and attendant unwanted side effects. Here, our approach targeted PDE–PK complexes as they would occur in signalosomes, thereby offering greater specificity. Our developed fluorescence polarization assay was adapted to identify inhibitors that block cyclic nucleotide pockets in PDE–PK complexes in one mode and disrupt protein-protein interactions between PDEs and PKs in a second mode. We tested this approach with three different systems—cAMP-specific PDE8–PKAR, cGMP-specific PDE5–PKG, and dual-specificity RegA–RD complexes—and ranked inhibitors according to their inhibition potency. Targeting PDE–PK complexes offers biochemical tools for describing the exquisite specificity of cyclic nucleotide signaling networks in cells. 相似文献
50.
Joseph Antony Eapen Merin K. Mampilly Maryann Ephraim Sajith V. 《Metallurgical and Materials Transactions A》2021,52(9):3689-3693
Metallurgical and Materials Transactions A - The present work compares the corrosion resistance properties of electrophoretically deposited MoS2 and WS2 nanosheets coatings on mild steel.... 相似文献