Tridentate Schiff base (H2fsal-β-ala) obtained from 3-formylsalicylic acid and β-alanine has been covalently bonded to divinylbenzene cross-linked chloromethylated polystyrene. This chelating resin, abbreviated as PS-H2fsal-β-ala (PS = polymeric support), reacts with vanadyl sulfate in DMF to give polymer bound complex, PS-[VO(fsal-β-ala) · DMF], formation of which has been confirmed by various physiochemical methods such as elemental analysis, FT-IR and diffused reflectance spectra, thermo gravimetric analysis, and scanning electron micrograph. Catalytic potential of PS-[VO(fsal-β-ala) · DMF] has been tested for the oxidation of various organic substrates such as benzene, cumene, naphthalene, cyclohexane, styrene, cyclohexene and trans-stilbene in the presence of 30% H2O2 as an oxidant. Oxidation products obtained from each substrate have been characterised by gas chromatography and their identities confirmed by gas chromatography–mass spectrometry. 相似文献
Cities in developing countries seldom consider the cost increases that regulations impose on development. To build legal housing, developers must meet a high minimum cost threshold established by mandatory standards. Many standards impose costs on building construction, make them less affordable to low-income households, deprive them access to legally built housing, and fuel the formation of slums. This study analyses the impact of relaxing a few mandatory building and site planning regulations on the cost of small two-room homes in Ahmedabad by developing two alternative layouts for the same site, one in accordance with prevalent regulations, and another after modifying a few regulations. It shows that rationalizing regulations can reduce housing cost by 34% and increase supply by as much as 75% without significantly lowering quality or compromising safety. It also shows that for a large portion of poor households, the costs imposed by mandatory standards are not trivial and have a high impact on the affordability of legally built housing. It recommends that if municipal authorities are interested in tackling the rapid growth of slums by expanding the supply of affordable housing, they should critically examine their building regulations and modify them to address the housing needs of their low-income residents. 相似文献
The interaction of the anthraquinone derivative mitoxantrone, a semisynthetic anti‐cancer drug with two non‐planar side chains, with heptamer G‐quadruplex d(TTAGGGT)4, which contains the human telomere DNA sequence, was evaluated by differential scanning calorimetry, fluorescence Job plotting, absorption, and NMR and CD spectroscopy. Binding led to thermal stabilization of DNA (ΔTm=13–20 °C). The spectra revealed that two mitoxantrone molecules bind externally at two sites of the DNA quadruplex as monomers, by partial insertion of the chromophore and side‐chain interaction at the grooves. The inhibition of telomerase (IC50=2 μm), as determined by a TRAP assay, can be attributed to thermal stabilization of the DNA quadruplex because of the interactions with mitoxantrone. The studies revealed highly specific molecular recognition between a ligand and a parallel‐stranded G‐quadruplex; this might serve as a platform for the rational design of new drugs. 相似文献
Delay tolerant networks (DTNs) are an emerging class of wireless networks which enable data delivery even in the absence of end-to-end connectivity. Under these circumstances, message replication may be applied to increase the delivery ratio. The requirement of long term storage and message replication puts a burden on network resources such as buffer and bandwidth. Buffer management is an important issue which greatly affects the performance of routing protocols in DTNs. Two main issues in buffer management are drop decision when buffer overflow occurs and scheduling decision when a transmission opportunity arises. The objective of this paper is to propose an enhancement to the Custom Service Time Scheduling traffic differentiation scheme by integrating it with a fuzzy based buffer ranking mechanism based on three message properties, namely, number of replicas, message size and remaining time-to-live. It uses fuzzy logic to determine outgoing message order and to decide which messages should be discarded within each traffic class queue. Results of simulation study show that the proposed fuzzy logic-based traffic differentiation scheme achieves improved delivery performance over existing traffic differentiation scheme for DTNs. 相似文献
VANET (Vehicular Ad Hoc Network) is a significant term in ITS (intelligent transportation systems). VANETs are also mentioned as ITN (intelligent transportation Networks), which are used to enhance road safety in growing technology. The connectivity of nodes is a challenging one because of its high mobility and the sparse network connectivity must be handled properly during its initial deployment of a VANET for avoiding accidents. Quality of service (QoS) in VANET becomes a significant term because of its increasing dare about unique features, like poor link quality, high mobility, and inadequate transporting distance. Routing is the foremost issue in the wireless ad hoc network, which is used to transmit data packets significantly. This paper provides a crucial review of the classification of existing QoS routing protocols, cross-layer design approach and classification, and various performance parameters used in QoS routing protocols. The corresponding cross-layer protocols are overviewed, followed by the major techniques in cross-layer protocol design. Moreover, VANET is presented with many exclusive networking research challenges in precise areas such as security, QoS, mobility, effective channel utilization, and scalability. Finally, the paper concluded by various comparison discussion, issues, and challenges of several routing protocols for VANET. No. of publications over the period from 2010 to 2019 in various scientific sources also showed in this review. This survey provided the technical direction for researchers on routing protocols for VANET using QoS.
International Journal of Coal Science & Technology - From the view of underground coal mining safety system, it is extremely important to continuous monitoring of coal mines for the prompt... 相似文献
Silicon - Tunnel Field Effect Transistor (TFET) is one of the most promising alternative device for semiconductor technology and shows better performance as compared to the conventional MOS device... 相似文献
The significance of this article lies in explaining the influence of Soret and Dufour numbers on an unsteady MHD free convection of flow of heat and mass transfer through porous media. The substances and radiation along the viscous, incompressible, and conductive compounds respond to the unstable convection of the liquid. Using physical quantities, the dimensional governing equations are converted to non-dimensional equations. Finite element Galerkin method is applied to numerically solve the resulting partial differential equations. Flow parameters on velocity, temperature, and concentration are studied and explained graphically to reflect their effects. Similarly, the skin friction number and Nusselt number are also observed and recorded in tables. 相似文献
In this paper, we propose a robust parametric twin support vector machine (RPTWSVM) classifier based on Parametric-\(\nu \)-Support Vector Machine (Par-\(\nu \)-SVM) and twin support vector machine. In order to capture heteroscedastic noise present in the training data, RPTWSVM finds a pair of parametric margin hyperplanes that automatically adjusts the parametric insensitive margin to incorporate the structural information of data. The proposed model of RPTWSVM is not only useful in controlling the heteroscedastic noise but also has much faster training speed when compared to Par-\(\nu \)-SVM. Experimental results on several machine learning benchmark datasets show the advantages of RPTWSVM both in terms of generalization ability and training speed over other related models. 相似文献
Breast cancer accounts for the first highest mortality rate in India and second in world. Though current treatment strategies are effectively killing cancer cells, they also end in causing severe side effects and drug resistance. Curcumin is a nutraceutical with multipotent activity but its insolubility in water limits its therapeutic potential as an anti‐cancer drug. The hydrophilicity of curcumin could be increased by nanoformulation or changing its functional groups. In this study, curcumin is loaded on mesoporous silica nanoparticle and its anti‐cancer activity is elucidated with MCF‐7 cell death. Structural characteristics of Mobil Composition of Matter ‐ 41(MCM‐41) as determined by high‐resolution transmission electron microscopy (HR‐TEM) shows that MCM‐41 size ranges from 100 to 200 nm diameters with pore size 2–10 nm for drug adsorption. The authors found 80–90% of curcumin is loaded on MCM‐41 and curcumin is released efficiently at pH 3.0. The 50 µM curcumin‐loaded MCM‐41 induced 50% mortality of MCF‐7 cells. Altogether, their results suggested that increased curcumin loading and sustained release from MCM‐41 effectively decreased cell survival of MCF‐7 cells in vitro.Inspec keywords: cancer, cellular biophysics, nanoparticles, nanomedicine, biomedical materials, polymers, mesoporous materials, transmission electron microscopy, drugs, adsorptionOther keywords: polyethylenimine‐modified curcumin‐loaded mesoporus silica nanoparticle, MCF‐7 cell line, breast cancer, cancer cells, drug resistance, multipotent activity, therapeutic potential, anticancer drug, mesoporous silica nanoparticle, MCF‐7 cell death, high‐resolution transmission electron microscopy, drug adsorption, curcumin‐loaded MCM‐41, nutraceutical curcumin, size 2 nm to 10 nm, size 100 nm to 200 nm相似文献