We describe here the synthesis of a novel magnetic drug-targeting carrier characterized by a core−shell structure. The core−shell carrier combines the advantages of a magnetic core and the ...stimuli-responsive property of the thermosensitive biodegradable polymer shell (e.g., an on−off mechanism responsive to external temperature change). The composite nanoparticles are ∼8 nm in diameter with ∼3 nm shell. The lower critical solution temperature (LCST) is ∼38 °C as determined by UV−vis absorption spectroscopy. The carrier is composed of cross-linked dextran grafted with a poly(N-isopropylacrylamide-co-N,N-dimethylacrylamide) dextran-g-poly(NIPAAm-co-DMAAm) shell and superparamagnetic Fe3O4 core. Fourier transform infrared spectroscopy (FTIR) confirmed the composition of the carrier. The synthesized magnetic carrier system has potential applications in magnetic drug-targeting delivery and magnetic resonance imaging.
Silica gel chitosan composite was prepared to perform adsorptive experiment of different heavy metal ion solutions. The characterization of chitosan + silica gel (Ch + Sg) composite was done by FTIR ...and SEM–EDS to understand the presence of active sites and to have an insight on the surface morphology. The adsorption study of heavy metal ions by Ch + Sg composite gives maximum removal percent for Cu, Pb and Ni which were obtained at pH 5 and for Hg at pH 6.The trend of removal by Ch + Sg signifies that maximum removal percent was attained at 120 min. The surface of Ch + Sg is heterogeneous for the adsorption of Hg, Ni and Cu and homogeneous for Pb adsorption. The values obtained for Pb signify that its adsorption best fitted to pseudo first order with the
R
2
value of 0.986, whereas pseudo second order best fitted to the experimental data of Cu, Ni and Hg as
R
2
values which are 0.983, 0.819 and 0.957 respectively. The values of change in entropy (⊿S) obtained for Pb, Cu, Ni and Hg are − 69.33, − 118, − 63.33 and − 98.52 J/mol K respectively. Negative values of change in enthalpy, ⊿H in (kJ/mol) are in the range of − 18.2 to − 37.66 which indicates both physical and chemical adsorption involves in the process of adsorption.
A
bstract
We propose simple scoto-seesaw models to account for dark matter and neutrino masses with spontaneous CP violation. This is achieved with a single horizontal
Z
8
discrete symmetry, broken ...to a residual
Z
2
subgroup responsible for stabilizing dark matter. CP is broken spontaneously via the complex vacuum expectation value of a scalar singlet, inducing leptonic CP-violating effects. We find that the imposed
Z
8
symmetry pushes the values of the Dirac CP phase and the lightest neutrino mass to ranges already probed by ongoing experiments, so that normal-ordered neutrino masses can be cornered by cosmological observations and neutrinoless double beta decay experiments.
A pH and thermo sensitive thin lipid layer coated mesoporous magnetic nanoassemblies (LMMNA) is presented for ‘on-demand’ release and delivery of dual cancer drugs. The synergistic effect of magnetic ...hyperthermia and dual chemotherapy was studied on various cancer cell lines. Display omitted
A new pH-sensitive and thermosensitive dual drug delivery system consisting of thin lipid layer encapsulated mesoporous magnetite nanoassemblies (MMNA) has been developed which can deliver two anticancer drugs simultaneously. The formulation of lipid layer used is 5:2:2:2w/w, DPPC:cholesterol:DSPE-PEG2000:MMNA. The structure, morphology and magnetic properties of MMNA and lipid coated MMNA (LMMNA) were thoroughly characterized. This hybrid system was investigated for its ability to carry two anticancer drugs as well as its ability to provide heat under an alternating current magnetic field (ACMF). A very high loading efficiency of up to ∼81% of doxorubicin hydrochloride (DOX) with an ∼0.02mgmg−1 loading capacity and ∼60% of paclitaxel (TXL) with an ∼0.03mgmg−1 loading capacity are obtained with LMMNA. A sustained release of drug is observed over a period of 172h, with better release, of ∼88:53% (DOX:TXL), at pH 4.3 compared to the ∼28:26% (DOX:TXL) in physiological conditions (pH 7.4). An enhanced release of ∼72 and ∼68% is recorded for DOX and TXL, respectively, during the first hour with the application of an ACMF (∼43°C). A greater in vitro cytotoxic effect is observed with the two drugs compared to them individually in HeLa, MCF-7 and HepG2 cancer cells. With the application of an ACMF for 10min, the cell killing efficiency is improved substantially due to simultaneous thermo- and chemotherapy. Confocal microscopy confirms the internalization of drug loaded MMNA and LMMNA by cells and their morphological changes during thermochemotherapy.
•Critically reviewed various processes for the recovery of Li from minerals and brines.•Heat treatment is required for liberating Li from the mineral lattice before leaching.•Solar evaporation of ...brine is crucial for Li enrichment to make the process viable.•Precipitation is extensively applied for the separation and purification of Li as Li2CO3.•SX/IX/RO/adsorption is being explored as an alternative for process enhancement.
Lithium (Li), an exceptional cathode material in rechargeable batteries, is an essential element in modern energy production and storage devices. The continuously increasing demand for lithium in these devices, along with their steady production, has led to the high economic importance of lithium, making it one of the strategically influential elements. The uneven distribution of mineral resources in the earth’s crust and the unequal concentration in brine and sea water reserves also causes lithium exploitation to be of critical importance. This situation requires the efficient processing of lithium resources either by the processing of minerals/brine/sea water or by the recycling of spent lithium-ion batteries. To explore new routes for the sustainable exploitation of lithium, it is imperative to review the methodologies that have already been studied and are currently in industrial practice. In this study, we present an overview of the processes investigated for the extraction, separation and recovery of lithium from not only a technological perspective but also from a chemical perspective.
In Part I, this state-of-the-art review addresses the processing of lithium resources that currently contributes to the commercial exploitation of this energy-critical element. This review includes lithium recovery from mineral (spodumene, petalite, lepidolite, zinnwaldite) and brine resources. A deliberation of the mineralogical aspect along with a review of the extraction process of lithium minerals is sub-divided according to the chosen media, namely, chloride, sulfate and carbonate, for their conversion into a leachable form, whereas the division of aqua-based resources is based on the lithium concentration. In the discussion, the advantages and/or disadvantages, problems and prospects of the processes are also summarized. We believe this article can contribute to improving the extraction and recovery processes of lithium toward the sustainability of this critical element and can provide future research directions.
•Exploitation of Lithium from sea water and spent batteries are critically reviewed.•Li recovery via adsorption and electrodialysis process from sea water is compared.•Pretreatment follows ...dismantling of LIBs to enrich the metals in black mass, LiMxOy.•Acid/alkali leaching followed by solvent extraction to separate the metals.•Precipitation is applied as a final step to get Li2CO3 from the both sources.
The uncertainty in production and utilization with the availability of lithium rich minerals and brine in a limited land area has grown the attention for the exploitation of those resources not coming under a specific boundary. Approximately 230 billion tons of lithium in ubiquitous sea water and generation of a huge amount of used lithium ion batteries (spent LIBs) in different corner of the end-user countries can play a major role to change the scenario of securing lithium as a raw material for industry. Therefore, it needs to be exploited in such an effective manner that it can assure the mitigation of projected supply risk of this energy-critical element. To explore the commercial viability for their sustainable exploitation, it is imperative to review the methodologies that have been investigated and have clear potential for upscaling.
This article deals with the processing of those resources that do not contributes yet to lithium supply in commodity market, and include the lithium recovery from sea water and spent LIBs. A purposive discussion on the electro-dialysis and reverse osmosis for the separation and recovery of lithium from sea water is of vital interest in future. A routinely disposed spent LIBs is a huge reservoir of lithium and need to be recovered as a main product along with the costlier cobalt, while recycling the spent LIBs. The various extraction and recovery processes of lithium are subdivided according to the adopted methodology, selection of lixiviant and obtaining the product in the desired form, whilst the technological and chemical perspective is also discussed. The deliberations on the edges and/or drawbacks, complications and prospects of the different processes are also included. It is believed that this state-of-the-art review can contribute in formulating the strategy for fulfilling the global energy demand by a sustainable recovery of lithium from its non-conventional resources, and can provide future research directions.
A simulation study based on water balance approach and field experimentation with rice-wheat cropping system was carried out by employing daily rainfall and evaporation (2002–2016) and edaphic data ...of Experimental Farm of the university, Pusa (25.98°N, 85.67°E, 52 m amsl), Bihar, situated under middle Indo-Gangetic Plains. The aims of the study were to optimize transplanting dates and assess irrigation requirement and water productivity of rice with a view to achieve climate smart rice-wheat production system. The suitability of advancing wheat planting under this cropping system was also evaluated for escaping terminal heat stress during reproductive to maturity period. Under rice-wheat system, late transplanting of rice during
kharif
season (monsoon season, synonymously also called as wet season) and, consequently, late planting of wheat during
rabi
(winter) season tend to reduce grain yield significantly under a set of adverse environmental conditions during flowering to maturity phases of both the crops. The study revealed that rice crop of 150-day duration (seed to seed) could be successfully transplanted early in th
e kharif
season during 20–30 June and be harvested by 25 October–5 November with the use of average 404–425-mm irrigation water to achieve potential yield and higher water productivity (1.648–1.731 kg m
−3
ha
−1
). Early rice harvesting ensured early completion of wheat planting before 15 November, which helped in escaping terminal high-temperature stress during the reproductive phase. Hence, higher system productivity can be achieved by shifting the planting dates of rice and wheat through optimum utilization of natural resource environment (moisture and thermal regimes) and offsetting the negative impacts of erratic monsoon rains on rice growth and terminal heat stress and hailstorm on subsequent wheat crop.
Catalytic co-pyrolysis of biomass and plastics (HDPE (high density polyethylene), PP (polypropylene) and PET (polyethylene terephthalate)) has been performed in a fixed-bed reactor in presence of ...cobalt based alumina, ceria and ceria-alumina catalysts to analyze the product distribution and selectivity. Catalysts are synthesized using co-precipitation method and characterized by BET (Brunauer–Emmett–Teller) surface area and XRD analysis. The effect of catalytic co-pyrolysis at different temperature with product distribution has been evaluated. The results have clearly shown the synergistic effect between biomass and plastics, the liquid products gradually increases forming with rise in the plastic content in the blend. Gaseous products have yielded most during pyrolysis of blend having biomass/plastics ratio of 5:1 with the presence of 40% Co/30% CeO2/30% Al2O3 catalyst with hydrogen gas production touched its peak of 47 vol%. Catalytic performance enhanced with increase with the cobalt loading, with best performance attributing to 40% Co/30% CeO2/30% Al2O3 catalyst.
•Catalytic co-pyrolysis of biomass and plastics (HDPE, PP & PET) blends in fixed-bed reactor.•Strong synergistic effect evident between biomass and plastics.•Solid residue diminished with application of catalysts.•Aromatics and olefins production increases with higher plastic content.•More hydrogen production with application of catalysts with higher cobalt content.
Nitrogen (N) plays an important role in agriculture crop production but the increasing application of nitrogen increases the possibilities of groundwater contamination through nitrate leaching. ...Nitrate leaching is the inevitable part of agriculture production which occurs during nitrogen fertilization. Hence, the quantification of nitrogen fertilizer is required to reduce nitrate leaching. In this study, nitrogen transformation and transport such as ammonium (NH4+) and nitrate (NO3−) at different soil depths and maize crop growth stages were measured during field experiments for two sowing dates (timely and delay) and four N fertilization levels under irrigated (year 2013 and 2014) and rainfed (year 2012 and 2014) conditions for maize crop. NH4+, NO3− and total nitrogen concentrations were measured using spectrophotometer at 410 nm and Kjeldahl method at varying soil depths and maize crop growth stages. Thereafter, nitrogen balance approach was used to estimate the NO3− leaching. Results indicated that NO3− leaching in irrigated condition was higher 109% in N75, 179% in N100, and 292% in N125 level respectively in comparison to the N0 level in timely sowing date, while in delayed sowing date, leaching was higher 54% in N75, 123% in N100, and 184% in N125 level respectively in comparison to N0 level. In rainfed, the NO3− leaching was higher 30% in N60, 59% in N80, and 99% in N100 level respectively in comparison to N0 level for the timely sowing date, while in delayed sowing, leaching was higher 23% in N60, 44% in N80, and 78% in N100 level respectively in comparison to N0 level. The results indicate that leaching losses were less in timely sowing dates for both rainfed and irrigated maize. The study further reveals that sowing dates combination with N levels could be an effective management strategy to reduce NO3− leaching by minimizing the N fertilization.
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•Ammonium and nitrate at different depths and crop growth stages were measured for irrigated and rainfed condition.•The concentration of NO3− was higher at the depth of 0–20 cm after application of fertilizer.•Delayed sowing reduced the nitrate loss during rainfed while vice versa in irrigated condition.•Optimum sowing time and nitrogen level can reduce the nitrate loss without affecting the grain yield.
N transformation & transport of NH4+ and NO3− at different soil depths in crop were measured for two sowing dates & four N fertilization levels under irrigated and rainfed conditions.
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