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An unprecedented protocol of visible-light-driven, organophotoredox/Mn dual catalyzed proton reduction for stereoselective semi-hydrogenation of alkynes is established.

A visible-light enabled, chemoselective photoreduction of 1,2-dicarbonyl compounds by using Hünig's base as reductant is reported.

The wavelength-regulated, methylene blue organic dye catalyzed stereodivergent synthesis of (Z)- and (E)-1,4-enediones from stabilized phosphorous ylides is reported. Broad ranges of substrates and functional groups are tolerated. Mechanistic studies suggested singlet-oxygen-promoted (E)-alkene formation via a possible phospha-1,2-dioxetane intermediate, followed by a blue-LED triggered (E) → (Z) isomerization reaction.

A resonance Rayleigh scattering (RRS) technique was utilized as a tool for isoelectric point monitoring and iron(III) cation determination. The spectral properties of some amphoteric molecules (proteins and a DNA sequence) were investigated using the RRS technique. When the pH values were kept at around their isoelectric points, especially high RRS signals could be obtained, which were much stronger than those at other pH values. By using the C30 DNA sequence as a probe, the iron(III) cation can be detected rapidly. After iron(III) was added to a C30 solution, a significantly decreased RRS signal was obtained. The sensing process can be finished within 10 min with a detection limit of 0.9 μM. Thus, a sensitive, selective, and label-free method was successfully developed for iron(III) detection.

Ascorbic acid (AA) is an important diet-derived antioxidant to human body. Thus, efficient and accurate detection of AA is of considerable significance in food analysis. Herein, smartphone assisted colorimetric and fluorescent triple-channel signal sensor has been developed for AA monitoring based on oxidase-like CoOOH nanoflakes. CoOOH nanoflakes can efficiently catalyze the oxidation of p-phenylenediamine (p-PD) into reddish brown p-PDox. The carbon dots (C-dots) are further introduced, of which the fluorescence can be quenched by p-PDox. However, in the presence of AA, the CoOOH nanoflakes is reduced and thus collapsed. As a result, the oxidation of p-PD is restrained, and thus the fluorescence of C-dots keeps strong. Based on AA induced light color, low absorbance, and strong fluorescence, triple-channel signal sensor has been proposed for AA determination. The AA assay shows a dynamic response range from 0.5 to 10 μM with a detection limit of 0.09 μM. The method assay allows detection of AA in real samples such as fruit juices. Combination with portable smartphone, the developed sensor is potential for AA determination in resource-poor settings.

Marsupenaneus japonicus is one of the important species in shrimp fisheries and aquaculture in China.Two morphologically similar varieties(Ⅰ and Ⅱ)with distinct color banding patterns on the carapace are recognized from the South China Sea.In the present study,9 pairs of microsatellite markers were used to detect the genetic diversities from two varieties of 6 wild stocks of M.japonicus,i.e.Zhoushan(ZS)stock in Zhejiang province,Xiamen(XM)stock in Fujian province,Huilai(HLQ and HLB)stock in Guangdong province,Lingshui(LS)stock in Hainan province and Beihai(BH)stock in Guangxi province.The results indicated:a total of 235 alleles were obtained from 9 markers in the 6 stocks.Polymorphic information content(PIC)value per locus was more than 0.5,indicating the 9 loci seemed highly polymorphic.Basic data statistics showed that the mean observed alleles in each stock were 13.2-17.7.The mean observed heterozygosity(Ho)ranged from 0.729 6 to 0.788 9 and the mean expected heterozygosity(He)ranged from 0.880 5 to 0.925 1.Average polymorphism information content(PIC)was 0.851 2-0.903 5,which explained high level of genetic diversity in 6 wild stocks.42.6% of stock loci showed significant deviation from the Hardy-Weinbery balance,and there was heterozygosity deficiency in all stocks.The pair-wise genetic differentiation(Fst)in 6 M.japonicus stocks ranged from 0.011 8 to 0.091 1,indicating significant genetic differentiation among the 6 stocks.Analysis of molecular variance(AMOVA)revealed that the variation within stocks was 93.06%,whereas the variation among stocks accounted for 6.94% of the total variation.The genetic distance among stocks ranged from 0.178 5 to 0.621 8.Cluster analysis based on DA indicated that HLB,BH and LS stocks were clustered as one group while ZS,XM and HLQ were gathered in another group.