Parameters extraction of single diode model of photovoltaic cell using improved firefly algorithm

Models of photovoltaic (PV) are significant in the design, study and control of renewable energy system. In these models, equivalent diode circuit model is widely researched and used because of its high precision. In diode circuit model, usually there are several parameters to be determined. To improve the performance of PV models, it is important to extract their unknown parameters exactly and quickly. However, because of the nonlinear of the V-I characteristic output of PV, it is difficult to obtain the parameters accurately. In this paper, a self-adaptive firefly algorithm is proposed to extract the parameters of single diode circuit model. Through introducing an adaptive mutation factor into the evolution process of a firefly algorithm, it improves the precision and stability of the solution. The proposed adaptive firefly algorithm is used to extract the parameters of single diode model which have 5 unknown parameters. By using measure output voltage and current data of PV, the proposed algorithm can extract parameters exactly and quickly. The proposed algorithm is compared with classic firefly algorithms and other algorithms in the paper. The results show that the effectiveness of the proposed algorithm

An economically viable PV hybrid micro-grid model for remote villages in developing countries

Africa contains a significant portion of the world’s population who are in energy poverty. The Sub-Saharan region, in particular, is laden with low electrification rates and high energy prices. This restricts affordable and reliable energy access, specifically in urban slums and rural communities. Decreasing component costs, such as photovoltaic (PV) modules have allowed for renewable energy systems to compete with fossil fuels and in some cases, can also gain an economic as well as environmental advantage. This study looks at the feasibility of incorporating PV into the many existing diesel-fueled mini-grids in Tanzania, offering a hybrid renewables-based system using HOMER software. Using the net present cost (NPC) and levelised cost of electricity (COE) designs were optimised to provide cleaner and cheaper electricity, when compared to the existing diesel counterparts. A hybrid PV-diesel system with battery storage proved the most economical with a COE of $0.29/kWh compared to the diesel-fueled COE of$0.35, a 16% decrease. The NPC for the hybrid model was $1,726,922 compared to$2,056,400 for the diesel model, proving the potential financial benefits of converting mini-grids across Tanzania to renewable energy

Electrochemical Acceptorless Dehydrogenation of N‑Heterocycles Utilizing TEMPO as Organo-Electrocatalyst

Catalytic acceptorless dehydrogenation (CAD) has been a basically important organic transformation to ubiquitous unsaturated compounds without the usage of a sacrificial hydrogen acceptor. In this work, we successfully developed the first electrochemical acceptorless dehydrogenation (ECAD) of N-heterocycles using TEMPO as the organo-electrocatalyst. We have achieved the catalytic dehydrogenation of N-heterocycles in an anode and the release of H₂ in a cathode using an undivided-cell system. A variety of six-membered and five-membered nitrogen-heteroarenes can be synthesized in good yields in this system. In addition, this protocol can also be used in the application of important molecular synthesis. Our electrochemical strategy provides a mild and metal-free route for (hetero)­aromatic compounds synthesis via the CAD strategy

Theoretical Insight into the Mechanism of Gold(I)-Catalyzed Rearrangement of 2‑Propargyl 2<i>H</i>‑Azirines to Pyridines

The title reaction is investigated in detail theoretically using density functional theory. After 5-<i>endo</i>-dig cyclization by nucleophilic attack, five possible pathways are taken into account in this work: direct ring expansion followed or accompanied by proton-transfer (paths A and B, respectively), 1,3-cationic migration (path C), proton-transfer before ring expansion (path D), and processing via a gold-nitrene (path E). Results indicate that the reaction would undergo the favored sequential pathway (path A) rather than other pathways. Moreover, the concerted mechanism (path B), which is designed to account for the selectivity of product in the experiment, would be unlikely in the reaction. The selectivity of product could be explained by the hindrance of ligand (<i>t</i>-BuXPhos) and the stability of the carbocation. Moreover, the binding energy of product complexes could account for the observed reaction rate

DataSheet1_The Research of Declining Factor and a New Model of Decline Rate for Gas Well Production in Low Permeability Reservoir.docx

The decline rate of gas wells varies with production time and is related to reservoir and working system. A typical single well numerical model of low permeability gas wells is established. The variation law of decline rate and its main influencing factors are studied by single factor analysis method. The results show that there are two stages of rapid and slow decline for the decline rate of gas wells, and the decline rate tends to be stable after the gas wells entering the decline period of 2–3 years; the decline rate increases with the increase of permeability, gas saturation and wellhead pressure, and decreases with the increase of porosity and well-controlled reserves; the decline rate in late production does not change with the change of reservoir thickness, initial production allocation and formation pressure. Then the decline rate model is and Then the decline rate model and the non-linear model of each factor are established by using response surface method are used to predict the decline rate quickly and accurately. According to the prediction model, the larger the well-controlled reserves, the smaller the permeability and the smaller the decline rate. In order to reduce production decline rate in gas well production process, it is suggested that the influence of various parameters on production decline rate should be considered comprehensively, and the well-controlled reserves of gas well should be increased as far as possible.</p

Table_1_Identification of novel SHANK2 variants in two Chinese families via exome and RNA sequencing.xlsx

BackgroundSHANK2 encodes a postsynaptic scaffolding protein involved in synapse formation, stabilization and homeostasis. Variations or microdeletions in the SHANK2 gene have been linked to a variety of neurodevelopmental disorders, including autism spectrum disorders (ASD) and mild to moderate intellectual disability (ID) in human. However, the number of reported cases with SHANK2 defects remains limited, with only 14 unrelated patients documented worldwide.MethodsIn this study, we investigated four patients from three families with ID. Whole-exome sequencing (WES) was performed to explore the genetic causes, while Sanger sequencing was used to confirm the identified variants. Furthermore, RNA sequencing and functional enrichment analysis were performed on patients with likely pathogenic variants to gain further insights into the molecular landscape associated with these variants.ResultsTwo novel variants in the SHANK2 gene: a heterozygous splicing substitution (NM_012309.5:c.2198-1G>A p.Pro734Glyfs*22) in Family 1, and a heterozygous nonsense variant [NM_012309.5:c.2310dupT p.(Lys771*)] in Family 2 were identified by WES and confirmed by Sanger sequencing. RNA sequencing and cohort analysis identified a total of 1,196 genes exhibiting aberrant expression in three patients. Functional enrichment analysis revealed the involvement of these genes in protein binding and synaptic functions.ConclusionWe identified two novel loss of function variants that broadens the spectrum of SHANK2 variants. Furthermore, this study enhances our understanding of the molecular mechanisms underlying SHANK2-related disorders.</p

Data_Sheet_1_Identification of novel SHANK2 variants in two Chinese families via exome and RNA sequencing.docx

BackgroundSHANK2 encodes a postsynaptic scaffolding protein involved in synapse formation, stabilization and homeostasis. Variations or microdeletions in the SHANK2 gene have been linked to a variety of neurodevelopmental disorders, including autism spectrum disorders (ASD) and mild to moderate intellectual disability (ID) in human. However, the number of reported cases with SHANK2 defects remains limited, with only 14 unrelated patients documented worldwide.MethodsIn this study, we investigated four patients from three families with ID. Whole-exome sequencing (WES) was performed to explore the genetic causes, while Sanger sequencing was used to confirm the identified variants. Furthermore, RNA sequencing and functional enrichment analysis were performed on patients with likely pathogenic variants to gain further insights into the molecular landscape associated with these variants.ResultsTwo novel variants in the SHANK2 gene: a heterozygous splicing substitution (NM_012309.5:c.2198-1G>A p.Pro734Glyfs*22) in Family 1, and a heterozygous nonsense variant [NM_012309.5:c.2310dupT p.(Lys771*)] in Family 2 were identified by WES and confirmed by Sanger sequencing. RNA sequencing and cohort analysis identified a total of 1,196 genes exhibiting aberrant expression in three patients. Functional enrichment analysis revealed the involvement of these genes in protein binding and synaptic functions.ConclusionWe identified two novel loss of function variants that broadens the spectrum of SHANK2 variants. Furthermore, this study enhances our understanding of the molecular mechanisms underlying SHANK2-related disorders.</p

Computational Design of Host Materials Suitable for Green-(Deep) Blue Phosphors through Effectively Tuning the Triplet Energy While Maintaining the Ambipolar Property

We theoretically designed a series of ambipolar host materials (<b>1</b>–<b>8</b>) which incorporate phosphine oxide and carbazole groups to the two ends of diphenyl (DP)-like bridges by para- and meta-connections, respectively. Density functional theory calculations were performed to investigate the influence of altering the DP-like bridges of these molecules on electronic structures and properties, and further to predict their performances as host materials in organic light-emitting diodes. The investigated results show the highest occupied molecular orbitals (HOMOs) and lowest unoccupied molecular orbitals (LUMOs) of <b>1</b>–<b>8</b>, distributed at the phenylcarbazole and the DP-like bridge, are responsible for hole and electron injection properties, respectively. The difference in the energies of HOMOs or LUMOs for <b>1</b>–<b>8</b> may be derived from different degrees of conjugation effect and electrostatic induction with altering the DP-like bridges of <b>1</b>–<b>8</b>. The singlet states (S₁), arising from the HOMO → LUMO transition, have intramolecular charge transfer character, which determines the small and different values of S₁ energies. On the other hand, altering the DP-like bridges brings a great effect on triplet exciton distributions, and consequently different triplet energies. The different singlet/triplet energies for <b>1</b>–<b>8</b> make hosts <b>1</b>–<b>8</b> suitable for four reference guests with green/deep-blue light when scientists consider the matching of host and guest in singlet/triplet energies for efficient energy transfer

AMPK mediates OA-NO₂-induced eNOS phosphorylation and NO production in BAECs.

<p>BAECs were treated with (<b>A</b>) different concentrations of OA-NO₂ for 16 h or (<b>B</b>) 2.5 µmol/L OA-NO₂ for the indicated times. Lysates were analyzed by western blot for the indicated proteins. The blot is representative of three blots obtained from three separate experiments. <b>C</b>) Western blot of phosphorylated AMPK and eNOS in OA-NO₂-stimulated BAECs infected with Ad-DN-AMPK (MOI = 50). Non-infected cells or cells infected with Ad-GFP served as controls. For <b>A–C</b>, the corresponding densitometric analyses are shown. *<i>p</i><0.05 <i>vs.</i> control; ^#<i>p</i><0.05 <i>vs.</i> GFP with OA-NO₂-treated group. <b>D</b>) NO release by OA-NO₂-stimulated BAECs infected with Ad-DN-AMPK (MOI = 50) or Ad-GFP (control). *<i>p</i><0.05 <i>vs.</i> non-transfected, no OA-NO₂ group; ^#<i>p</i><0.05 <i>vs.</i> OA-NO₂-treated, Ad-GFP group. <b>E</b>) AMPK activity corresponding to <b>C</b> and <b>D</b> above. *<i>p</i><0.05 <i>vs.</i> no OA-NO₂ treatment, Ad-GFP group; ^#<i>p</i><0.05 <i>vs.</i> OA-NO₂-treated, Ad-GFP group. <b>F</b>) The proposed signaling pathway involved in AMPK/eNOS activation in response to OA-NO2 treatment in endothelial cells.</p

Induction of HO-1 protein and AMPK activation by OA-NO₂.

<p><b>A</b>) BAECs were incubated with OA-NO₂ at the indicated concentrations or with BSA (vehicle) for 16 h, and western blot analysis was performed as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0031056#s4" target="_blank">Materials and Methods</a> to detect HO-1 protein expression and AMPK phosphorylation at Thr172. The blot is representative of those obtained from three separate experiments. Corresponding densitometric analyses of phosphorylated AMPK and ACC are shown. *<i>p</i><0.05 <i>vs.</i> control. <b>B</b>) BAECs were incubated with 2.5 µM OA-NO₂ for the indicated times, and western blotting was performed as above. The blot is representative of three blots obtained from three separate experiments. *<i>p</i><0.05 <i>vs.</i> corresponding control. <b>C</b>) Confluent BAECs were exposed to vehicle or OA-NO2 (2.5 µM) for 16 h. AMPKα was immunoprecipitated from cell lysates (1 mg) with a specific antibody. AMPK activity was assayed by ³²P-ATP incorporation into the SAMS peptide. *<i>p</i><0.05 <i>vs.</i> control. <b>D</b>) BAECs were incubated with the indicated concentrations of OA for 16 h. Western blotting was performed as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0031056#s4" target="_blank">Materials and Methods</a>. <b>E</b>) BAECs were infected with Ad-DN-AMPK (MOI = 50) or Ad-GFP (control). Infected and non-infected cells were treated with 2.5 µM OA-NO₂ for 16 h. AICAR and metformin were used as positive controls. The blot is representative of three blots obtained from three separate experiments.</p