Machine learning techniques for prediction of capacitance and remaining useful life of supercapacitors: A comprehensive review

Supercapacitors are appealing energy storage devices for their promising features like high power density,outstanding cycling stability,and a quick charge–discharge cycle.The exceptional life cycle and ultimate power capability of supercapacitors are needed in the transportation and renewable energy generation sectors.Hence,predicting the capacitance and lifecycle of supercapacitors is significant for selecting the suitable material and planning replacement intervals for supercapacitors.In addition,system failures can be better addressed by accurately forecasting the lifecycle of SCs.Recently,the use of machine learning for performance prediction of energy storage materials has drawn increasing attention from researchers globally because of its superiority in prediction accuracy,time efficiency,and costeffectiveness.This article presents a detailed review of the progress and advancement of ML techniques for the prediction of capacitance and remaining useful life(RUL)of supercapacitors.The review starts with an introduction to supercapacitor materials and ML applications in energy storage devices,followed by workflow for ML model building for supercapacitor materials.Then,the summary of machine learning applications for the prediction of capacitance and RUL of different supercapacitor materials including EDLCs(carbon based materials),pesudocapacitive(oxides and composites)and hybrid materials is presented.Finally,the general perspective for future directions is also presented.

Memory-Type Control Charts Through the Lens of Cost Parameters

A memory-type control chart utilizes previous information for chart construction.An example of a memory-type chart is an exponentially-weighted moving average(EWMA)control chart.The EWMA control chart is well-known and widely employed by practitioners for monitoring small and moderate process mean shifts.Meanwhile,the EWMA median chart is robust against outliers.In light of this,the economic model of the EWMA and EWMA median control charts are commonly considered.This study aims to investigate the effect of cost parameters on the out-of-control average run lengthðARL_(1)Þin implementing EWMA and EWMA median control charts.The economic model was used to compute the ARL_(1) parameter.The 14 input parameters were identified and the analysis was carried out based on the one-parameter-at-a-time basis.When the input parameters change based on a predetermined percentage,the ARL_(1) is affected.According to the results of the EWMA chart,nine input parameters had an effect andfive input parameters had no effect on the ARL_(1) parameter.Further,only seven of the 14 input parameters had an effect on the ARL_(1) of the EWMA median chart.However,the effect of each input parameter on the ARL_(1) was different.Moreover,the ARL_(1) for the EWMA median chart was smaller than the EWMA chart.This analysis is crucial to observe and determine the input parameters that have a significant impact on the ARL_(1) of the EMWA and EWMA median control charts.Hence,practitioners can obtain an overview of the influence of the input parameters on the ARL_(1) when implementing the EWMA and EWMA median control charts.

Spectroscopic analysis on the binding interaction of biologically active pyrimidine derivative with bovine serum albumin

A biologically active antibacterial reagent, 2–amino-6-hydroxy–4–(4-N, N-dimethylaminophenyl)-pyrimidine-5-carbonitrile(AHDMAPPC), was synthesized. It was employed to investigate the binding interaction with the bovine serum albumin(BSA) in detail using different spectroscopic methods. It exhibited antibacterial activity against Escherichia coli and Staphylococcus aureus which are common food poisoning bacteria. The experimental results showed that the fluorescence quenching of model carrier protein BSA by AHDMAPPC was due to static quenching. The site binding constants and number of binding sites(n E 1) were determined at three different temperatures based on fluorescence quenching results. The thermodynamic parameters, enthalpy change(ΔH), free energy(ΔG) and entropy change(ΔS) for the reaction were calculated to be 15.15 k J/mol, –36.11 k J/mol and 51.26 J/mol K according to van't Hoff equation, respectively. The results indicated that the reaction was an endothermic and spontaneous process, and hydrophobic interactions played a major role in the binding between drug and BSA. The distance between donor and acceptor is 2.79 nm according to F?rster's theory. The alterations of the BSA secondary structure in the presence of AHDMAPPC were confirmed by UV–visible, synchronous fluorescence, circular dichroism(CD) and three-dimensional fluorescence spectra. All these results indicated that AHDMAPPC can bind to BSA and be effectively transported and eliminated in the body. It can be a useful guideline for further drug design.

用椰壳制活性炭吸附去除三价铋离子(英文)

In present study,we report the preparation of coconut shell activated carbon as adsorbent and its appli-cation for Bi(Ⅲ) removal from aqueous solutions.The developed adsorbent was characterized with scanning elec-tron microscope(SEM),Fourier Transform Infrared(FTIR),C,H,N,S analyzer,and BET surface area analyzer.The parameters examined include agitation time,initial concentration of Bi(Ⅲ),adsorbent dose and temperature.The maximum adsorption of Bi(Ⅲ)(98.72%) was observed at 250 mg·L-1 of Bi(Ⅲ) and adsorbent dose of 0.7 g when agitation was at 160 r·min-1 for 240 min at(299±2) K.The thermodynamic parameters such as Gibb's free energy(△Gθ),enthalpy(△Hθ) and entropy(△Sθ) were evaluated.For the isotherm models applied to adsorption study,the Langmuir isotherm model fits better than the Freundlich isotherm.The maximum adsorption capacity from the Langmuir isotherm was 54.35 mg?g?1 of Bi(Ⅲ).The kinetic study of the adsorption shows that the pseudo second order model is more appropriate than the pseudo first order model.The result shows that,coconut shell ac-tivated carbon is an effective adsorbent to remove Bi(Ⅲ) from aqueous solutions with good adsorption capacity.

Photoelectrocatalytic activity of immobilized Yb doped WO3 photocatalyst for degradation of methyl orange dye

Pure WO_3 and Yb:WO_3 thin films have been synthesized by spray pyrolysis technique. Effect of Yb doping concentration on photoelectrochemical, structural, morphological and optical properties of thin films are studied. X-ray diffraction analysis shows that all thin films are polycrystalline nature and exhibit monoclinic crystal structure. The 3 at% Yb:WO_3 film shows superior photoelectrochemical(PEC) performance than that of pure WO_3 film and it shows maximum photocurrent density(Iph= 1090 μA/cm^2) having onset potentials around +0.3 V/SCE in 0.01 M HClO_4. The photoelectrocatalytic process is more effective than that of the photocatalytic process for degradation of methyl orange(MO) dye. Yb doping in WO_3 photocatalyst is greatly effective to degrade MO dye. The enhancement in photoelectrocatalytic activity is mainly due to the suppressing the recombination rate of photogenerated electron-hole pairs. The mineralization of MO dye in aqueous solution is studied by measuring chemical oxygen demand(COD) values.

在L-缬氨酸介质中应用聚二苯并-18-冠醚-6分离铈(Ⅲ)(英文)

A column chromatographic method has been developed for the separation and determination of cerium(Ⅲ) using poly[dibenzo-18-crown-6].The separation was carried out in L-valine medium.The adsorption of cerium(Ⅲ) was quantitative from 1×10-1 to 1×10-4 mol/L L-valine.Amongst the various eluents,1.0-8.0 mol/L hydrochloric acid,1.0-8.0 mol/L hydrobromic acid,1.0-8.0 mol/L perchloric acid,1.0-2.0 mol/L sulfuric acid and 4.0-5.0 mol/L acetic acid,were found to be the efficient eluents for cerium(Ⅲ).The capacity of poly[dibenzo-18-crown-6] for cerium(Ⅲ) was(0.428±0.01) mmol/g.The method was applied to the separation of cerium(Ⅲ) from associated elements link uranium(Ⅵ) and thorium(Ⅳ).It was also applied for the determination of cerium(Ⅲ) in geological samples.The method is simple,rapid and selective with good reproducibility(approximately±2%).

Recent Progress in Preparation of Superhydrophobic Surfaces: A Review

In nature, water-repellency (superhydrophobicity) is found, besides in plants, in insects and bird feathers. The booming field of biomimetics allows one to mimic nature to develop nanomaterials, nanodevices, and processes which offer desirable properties. Biomimetics means mimicking biology or nature. Inspired from nature, which reveals excellent superhydrophobicity, researchers have recently developed and implemented biomimetic superhydrophobic surfaces in a variety of smart and simple ways. Superhydrophobicity is an effect where surface roughness and chemical composition combine to generate unusual water repellent surface, causing water to bounce and roll off the surface. This review article provides the overview of the recent progress (within the last four years) in the synthesis, characterization, theoretical modelling, and applications of superhydrophobic surfaces, with focus on the different techniques used and how they have developed over the years. At last, the difficulties related to implementation of superhydrophobic surfaces in day to day life are discussed. This review can find interesting for students, scientists and industrial companies working especially on superhydrophobic surfaces.

Lanthanum(Ⅲ) sorption studies on poly[dibenzo-18-crown-6] and its separation from uranium(Ⅵ) and thorium(Ⅳ) in L-valine medium

The sorption study of La(Ⅲ) was carried out on poly[dibenzo-18-crown-6] and L-valine medium. The quantitative adsorption of La(Ⅲ) was found at 1×10-2 to 1×10-5 mol/L L-valine. The various eluting agents were found efficient eluents for La(Ⅲ). The capacity of crown polymer for La(Ⅲ) was found to be 0.43 ±0.01 mmol/g. The tolerance limit of various cations and anions for La(Ⅲ) was determined. La(Ⅲ) was quantitatively separated from other metal ions in binary as well as multicomponent mixtures. The study was extended to sequential separation of La(Ⅲ), U(VI) and Th(IV). The good separation yields were obtained and had good reproducibility (±2%). The method incorporated the determination of La(Ⅲ) in real sample. The method was simple, rapid and selective.

A symmetric MnO_2/MnO_2 flexible solid state supercapacitor operating at 1.6V with aqueous gel electrolyte

The demand of microelectronic devices postulated high energetic flexible energy storage devices. Flexible solid state supercapacitor is flawless possible candidate to fulfill the requirement of microelectronic devices. This investigation provides practical evidence of the use of flexible solid state supercapacitors based on MnO_2 electrodes with polyvinylpyrrolidone(PVP)-Li ClO_4 gel electrolyte. Initially, different acid mediated growths of MnO_2 have been carried. Later, the electrochemical performances of MnO_2 electrodes have been carried out. Impressively, the fabricated symmetric flexible solid state supercapacitor(FSS-SC) device demonstrates the highest operating potential window of 1.6 V with extended cycling stability. Moreover, the cell exhibits high energy density of 23 Wh/kg at power density of 1.9 k W/kg. It is interesting to note that the device shows excellent flexibility upon bending at angle of 180° for number of times. These results clearly evidenced those symmetric FSS-SC devices based on MnO_2 electrodes are promising energy storage devices for microelectronic applications.

Influence of rare-earth ions on structural and magnetic properties of CdFe_2O_4 ferrites

Nano-sized powders of rare-earth ions added CdFe2O4 ferrites were synthesized by oxalate co-precipitation method.The influence of R ions(R = Sm3+, Y3+, and La3+) on the microstructure and magnetic properties of CdFe2O4 ferrites was studied.XRD, SEM, FTIR, and magnetic hysteresis loops were used for analyzing the samples.The addition of R ions alters the structure of the powders and decreases the crystalline size, lattice constant, and grain size.The magnetic properties such as saturation magnetization, remanent magnetization, and magnetic moment increased due to addition of rare-earth ions in CdFe2O4 ferrite.The formation of secondary phase on the grain boundaries supports the abnormal growth.FTIR spectra show two absorption bands.Results suggest that the magnetic properties depend on the particular method of preparation and additives.

Biological sources of L-DOPA: An alternative approach

Parkinson’s disease was first formally identified by British physician James Parkinson in 1817 as “The Shaking Palsy”. L-DOPA (3,4-dihydroxy-phenyl-L-alanine) has been considered as a gold-standard treatment for Parkinson’s disease. The world market for L-DOPA is about 250 t/year and the total market volume is about $101 billion per year. The present review summarizes the different biological sources for the production of L-DOPA. The process for L-DOPA production from different biological sources has advantages over the chemical methods such as, enantiometrically pure L-DOPA, less incubation time and cost effective method. L-DOPA is found naturally in certain plant foods, particularly broad beans which found to replenish brain levels of L-DOPA even more quickly, and for longer periods, than conventional medication.

Graphene-wrapped Ag3PO4/LaCO3OH heterostructures for water purification under visible light

We demonstrated a unique synthesis approach of graphene(GR)-wrapped Ag_3PO_4/LaCO_3OH(APO/LCO)heterostructures by an in-situ wet chemical method. FESEM analysis reveals the formation of rhombic dodecahedrons of APO decorated with LCO and later wrapped with GR flakes. Optical studies shows two absorption edges corresponding to the band gap energies of APO(2.41 eV) and LCO(4.1 eV). Considering the absorption edge of the heterostructures in the visible region, the photocatalytic activities of photocatalysts containing different APO/LCO mass ratios were evaluated by the degradation of MB. GR-decorated composite with 20% LCO(APO/LCO20/GR) exhibited the highest photocatalytic activity for MB degradation, with a rate constant, k of 0.541 min^(-1). The photocatalytic activity of APO/LCO20/GR more greatly enhanced than those of the individual constituents(APO, LCO, APO/LCO20). The enhanced photocatalytic activity of the heterostructure can be attributed to the co-catalytic effect of LCO as well as intriguing physicochemical properties of GR. To understand the enhanced photocatalytic activity of the heterostructures the photocatalytic reaction mechanism is proposed in detail. The recyclability of the APO/LCO/GR composite photocatalyst is further evaluated by reusing the catalyst in replicate photocatalytic experiments which shows consistent photocatalytic activity thereby confirms the stability and reusability of heterostructure photocatalyst.

Mesoporous cadmium bismuth niobate(CdBi2Nb2O9)nanospheres for hydrogen generation under visible light

Herein, we report visible light active mesoporous cadmium bismuth niobate(CBN) nanospheres as a photocatalyst for hydrogen(H_2) generation from copious hydrogen sulfide(H_2S). CBN has been synthesized by solid state reaction(SSR) and also using combustion method(CM) at relatively lower temperatures.The as-synthesized materials were characterized using different techniques. X-ray diffraction analysis shows the formation of single phase orthorhombic CBN. Field emission scanning electron microscopy and high resolution-transmission electron microscopy showed the particle size in the range of ~0.5–1 μm for CBN obtained by SSR and 50–70 nm size nanospheres using CM, respectively. Interestingly, nanospheres of size 50–70 nm self assembled with 5–7 nm nanoparticles were observed in case of CBN prepared by CM.The optical properties were studied using UV–visible diffuse reflectance spectroscopy and showed band gap around ~3.0 eV for SSR and 3.1 eV for CM. The slight shift in band gap of CM is due to nanocrystalline nature of material. Considering the band gap in visible region, the photocatalytic activity of CBN for hydrogen production from H_2S has been performed under visible light. CBN prepared by CM has shown utmost hydrogen evolution i.e. 6912 μmol/h/0.5 g which is much higher than CBN prepared using SSR.The enhanced photocatalytic property can be attributed to the smaller particle size, crystalline nature,high surface area and mesoporous structure of CBN prepared by combustion method. The catalyst was found to be stable, active and can be utilized for water splitting.

CdS nanocrystals as fluorescent probe for detection of dolasetron mesylate in aqueous solution:Application to biomedical analysis

A simple and straightforward method for the determination of dolasetron mesylate(DM) in aqueous solution was developed based on the fluorescence quenching of 3-Mercaptopropionic acid(MPA) capped Cd S quantum dots(QDs).The structure,morphology,and optical properties of synthesized QDs were characterized by using UV-Vis absorption spectroscopy,fluorescence spectroscopy,transmission electron microscopy(TEM) and dynamic light scattering(DLS) measurements.Under the optimum conditions,the MPA-Cd S QDs fluorescence probe offered good sensitivity and selectivity for detecting DM.The probe provided a highly specific selectivity and a linear detection of DM in the range of 2–40 μg/m L with detection limit(LOD) 1.512 μg/m L.The common excipients did not interfere in the proposed method.The fluorescence quenching mechanism of Cd S QDs is also discussed.The developed sensor was applied to the quantification of DM in urine and human serum sample with satisfactory results.

Evaluation of L-dopa,proximate composition with in vitro anti-inflammatory and antioxidant activity of Mucuna macrocarpa beans:A future drug for Parkinson treatment

Objective: To investigate L-3, 4-dihydroxyphenylalanine(L-dopa, anti-Parkinson drug),anti-inflammatory activity, proximate nutritional composition and antioxidant potential of Mucuna macrocarpa(M. macrocarpa) beans.Methods: L-dopa content was determined and quantified by high performance thin layer chromatography and reversed phase high-performance liquid chromatography(RPHPLC) methods. Anti-inflammatory activity was performed by in vitro protein denaturation inhibition and human red blood cell membrane stabilisation activity. Proximate composition and elemental analysis were also investigated. The antioxidant potential(2,2-diphenyl-1-picrylhydrazyl, N-N-dimethyl-phenylenediamine and ferric-reducing antioxidant power) of M. macrocarpa beans were evaluated by using different extraction solvents. The RP-HPLC analysis also quantified significant phenolics such as gallic acid, tannic acid, p-hydroxybenzoic acid and p-coumaric acid.Results: RP-HPLC quantification revealed that M. macrocarpa beans contain a high level of L-dopa [(115.41 ± 0.985) mg/g] which was the highest among the Mucuna species from Indian sub-continent. Water extract of seed powder showed strong antiinflammatory and antioxidant potential. Proximate composition of M. macrocarpa beans revealed numerous nutritional and anti-nutritional components. RP-HPLC analysis of major phenolics such as tannic acid(43.795 mg/g), gallic acid(0.864 mg/g), p-coumaric acid(0.364 mg/g) and p-hydroxybenzoic acid(0.036 mg/g) quantified successfully from M. macrocarpa beans respectively.Conclusions: This study suggests that M. macrocarpa is a potential source of L-dopa with promising anti-inflammatory, antioxidant and nutritional benefits.

Innovative use of intact seeds of Mucuna monosperma Wight for improved yield of L-DOPA

The drug L-DOPA has been widely used against Parkinson's disease and is extracted from plants.Due to the increasing demand of this drug,new plant sources need to be discovered in addition to the existing sources.The paper embodies results on Mucuna monosperma,which can be a promising candidate for L-DOPA.The seed powder of this plant contains 5.48%of(dry weight)the drug and when the seeds were soaked in distilled water,content was increased to 6.58%.Different elicitors when added,enhanced the drug level in seed up to 11.8%.The possible rationale behind this increase was confirmed by increase in tyrosinase activity in the seeds.Presence of L-DOPA was confirmed using various analytical techniques as HPLC,HPTLC and NMR.The work demonstrates a potential candidate plant as a source for L-DOPA when a novel method was adopted as described here.

Pharmaceutical and nutraceutical potential of natural bioactive pigment:astaxanthin

Astaxanthin(3,3′-dihydroxy-β,β-carotene-4,4′-dione)is an orange-red,lipophilic keto-carotenoid pigment.It is majorly found in marine ecosystems particularly in aquatic animals such as salmon,shrimp,trout,krill,crayfish,and so on.It is also synthesized in microalgae Heamatococcus pluvialis,Chlorococcum,Chlorella zofingiensis,red yeast Phaffia rhodozyma and bacterium Paracoccus carotinifaciens.Some aquatic and terrestrial creatures regarded as a primary and secondary sources of the astaxanthin producing and accumulating it through their metabolic pathways.Astax-anthin is the powerful antioxidant,nutritional supplement as well as promising therapeutic compound,observed to have activities against different ravaging diseases and disorders.Researchers have reported remarkable bioactivities of astaxanthin against major non-communicable chronic diseases such as cardiovascular diseases,cancer,diabetes,neurodegenerative,and immune disorders.The current review discusses some structural aspects of astaxanthin.It fur-ther elaborates its multiple potencies such as antioxidant,anti-inflammatory,anti-proliferative,anti-cancer,anti-obese,anti-diabetic,anti-ageing,anti-TB,anti-viral,anti-COVID 19,neuro-protective,nephro-protective,and fertility-enhanc-ing properties.These potencies make it a more precious entity in the preventions as well as treatments of prevalent systematic diseases and/or disorders.Also,the review is acknowledging and documenting its powerful bioactivities in relation with the pharmaceutical as well as nutraceutical applicability.

Evaluation of Various Factors Affecting Bioconversion of L-Tyrosine to L-DOPA by Yeast Yarrowia lipolytica-NCIM 3450 Using Response Surface Methodology

3,4-Dihydroxy L-phenylalanine(L-DOPA)is considered a potent drug for the treatment of Parkinson disease.Physical and nutritional parameters where optimized by using Yarrowia lipolytica-NCIM 3450 to accomplished the highest production of L-DOPA.Screenings of critical components were completed by using a Plackett–Burman design,while further optimization was carried out using the Box–Behnken design.The optimized factor levels predicted by the model were pH 6.1,1.659 g L^(-1)yeast extract,1.491 g L^(-1)L-tyrosine and 0.0290 g L^(-1)CuSO4.The predicted yield of L-DOPA with these levels was 1.319 g L^(-1),while actual yield obtained was 1.273 g L^(-1).The statistical analysis revealed that model is significant with F value 19.55 and R2 value 0.9514.This process resulted in a 3.594-fold increase in the yield of LDOPA.L-DOPA was confirmed by HPTLC and HPLC analysis.Thus,Yarrowia lipolytica-NCIM 3450 has potential to be a new source for the production of L-DOPA.

Magnetoelectric Coupling in Metglas/BaTiO3/Metglas Lead-Free Magnetoelectric Composites

We report the magnetoelectric (ME) coupling in ME composites composed of NiFe2O4 (NFO) or metglas as magnetostrictive phases and BaTiO3 (BTO) as piezoelectric phase, targeting lead free magetnic field sensors. NFO and BTO phases were synthesized by solid state sintering method and further characterized by using XRD and FESEM techniques. The P-E hysteresis curve shows good ferroelectric behavior with saturation polarization of Ps = 15.87 C/cm2 and coercive electric field of 130 kV/cm. The ME response was characterized as a function of dc magnetic field at a fixed frequency. The transverse ME voltage coefficient, αME31 shows 2 times larger magnitude than that of longitudinal ME voltage coefficient, αME31. The maximum αME31 of 37 mV/cm•Oe (@Hdc = 250 Oe) is observed for NFO/BTO/NFO ME composites with thickness ratio of tm/tp = 1.0. The ME coupling is further enhanced by replacing NFO layers by highly magnetostrictive metglas layers. Metglas/BTO/metglas laminates show large αME31 value of 81 mV/cm•Oe at relatively lower Hdc of 145 Oe. The present laminates can offer promising opportunities of engineering environmental friendly ME laminate for applications in ME devices such as energy harvester and magnetic field sensors.