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The selective recognition of target ions in water is very important and the development of novel water-soluble chemosensor is still an intriguing challenge. Herein, a novel water-soluble fluorescent sensor based on aspartic acid (Asp) functionalized 1,8-naphthalimide derivative (Asp-NI) has been designed and synthesized. The sensor Asp-NI could dissolve in water and successively detect Fe3+ and H2PO4− in water solution with high selectivity and sensitivity. The detection limits are 4.97 × 10−7 mol/L for Fe3+ and 5.27 × 10−6 mol/L for H2PO4−. Other coexistent competitive metal ions (Hg2+, Ag+, Ca2+, Cu2+, Co2+, Ni2+, Cd2+, Pb2+, Zn2+, Cr3+, and Mg2+) showed no interference in the Fe3+ detection process. The sensor Asp-NI could act as a Fe3+ and H2PO4− controlled “On–Off–On” fluorescent switch. More interestingly, the Fe3+ induced fluorescence quenching process could be totally reversed by the addition of H2PO4−, this “On–Off–On” switching process could be repeated several times with little fluorescence loss. Notably, the actual usage of sensor Asp-NI was further demonstrated by test kits.

A colorimetric and fluorescent probe L has been designed and synthesized, which bearing the double azine moiety and showing a detection limit of 2.725 × 10−7 M towards Zn2+. Based on the basic recognition mechanism of ESIPT and CHEF effect, the L has high selectivity and sensitivity to only Zn2+ (not Fe3+, Hg2+, Ag+, Ca2+, Co2+, Ni2+, Cd2+, Pb2+, Cr3+, and Mg2+) within the physiological pH range (pH = 7.0–8.4) and showed a fluorescence switch. Moreover, this detection progress occured in the DMSO/H2O ∼ HEPES buffer (80/20, v/v; pH 7.23) solution which can conveniently used on test strip., Graphical abstract A colorimetric and fluorescent probe L has been designed and synthesized, bearing the double azine moiety and showing a detection limit of 2.725 × 10−7 M towards Zn2+. Based on the basic recognition mechanism of ESIPT and CHEF effect, the probe owes high selectivity and sensitivity to only Zn2+ (not Fe3+, Hg2+, Ag+, Ca2+, Co2+, Ni2+, Cd2+, Pb2+, Cr3+, and Mg2+) within the physiological pH range (pH = 7.0–8.4) and showed a fluorescence switch. Moreover, this detection progress occur in the DMSO/H2O ∼ HEPES buffer (80/20, v/v; pH 7.23) solution which can conveniently used on test strip, and it can anti interference of others.Image 1

In this paper, a new method that extracting and fixing load characteristic curve in the power system network state estimation is proposed, based on the combination of The data mining technology in the critical meams assorts algorithm and effective index standards. In the course of the study, this paper put forward a new algorithm ,which simulates used matlab software programming and combined with the actual load data, and extracts load characteristic curve for amended. Revised characteristic curve will serve as a typical load model used to add system state estimation of pseudo measure. The simulation results fully support that the proposed method is rational and effective.

In this paper, based on the choice of voltage level 500kV for large transformer differential protection of maloperation accident actually as an example, discusses how to improve the reliability and the transformer differential protection with the relationship between pressure test. Analysis found that in order to avoid the excitation transient exciting current transformer differential protection sparked the misoperation, on-site technical personnel in the differential protection setting calculation process, make use of data in conformity with the relevant parameters, rules and standards, familiar with differential protection, also need to understand the characteristics of transformer excitation transient exciting current high-voltage tests, the influence of characteristic more should fully exert the modern PC wave record device, instrument function can improve the actual effect of transformer differential protection. This factory for transformer differential protection for setting, protection greatly improves the reliability. This experience is worth popularizing.

To determine whether the matrix metalloproteinase 9 gene (MMP9) polymorphism is associated with the onset or progression of adolescent idiopathic scoliosis (AIS) in Chinese Han female.Three single nucleotide polymorphisms (SNPs) (rs17576, rs2250889, rs1805088) were genotyped through TaqMan-based real-time PCR assay in 190 AIS patients and 190 controls, all of whom were females from Chinese Han population with matched age. Analyses performed included Hardy Weinberg equilibrium test, Pearson chi-square test, Logistic regression analysis, linkage disequilibrium analysis and haplotype analysis. The mean maximum Cobb angles with different genotypes in case-only dataset were also compared.All 3 SNPs have reached Hardy-Weinberg equilibrium in the controls. Genotype and allele frequencies of all SNPs were found similar between cases and controls by Pearson chi-square test and Logistic regression. Genotype-phenotype analysis showed that patients with CC genotype in rs2250889 featured larger maximum Cobb angles.MMP9 may not be a predisposition gene of AIS in Han female. However, homozygous mutation in rs2250889 can render scoliosis more severe, implying that MMP9 defect may result in deterioration of AIS.