Phosphorus speciation and colloidal phosphorus responses to short-term cessation of fertilization in a lime concretion black soil

Long-term excessive application of mineral fertilizer has led to soil acidification and phosphorus(P) accumulation, increasing the risk of P loss and environmental pollution, and cessation of fertilization is widely considered as a cost-effective management strategy to relieve this situation;however, how such cessation influences P speciation and concentrations in a bulk soil and colloidal fractions and whether decreasing P concentration might maintain soil fertility remain unclear. In this study, the effects of long-term fertilization(ca. 40 years) and short-term cessation of fertilization(ca. 16 months) on inorganic, organic,and colloidal P in lime concretion black soil were investigated using P sequential fractionation and31P nuclear magnetic resonance spectroscopy. After long-term fertilization, available P, dicalcium phosphate, iron-bound P, orthophosphate monoesters, and orthophosphate diesters increased significantly, but soil p H decreased by ca. 2.8 units, indicating that long-term fertilization caused soil acidification and P accumulation and changed P speciation markedly. In contrast, short-term fertilization cessation increased soil p H by ca. 0.8 units and slightly reduced available and inorganic P. Available P after fertilization cessation was 22.9–29.8 mg kg-1, which was still sufficient to satisfy crop growth requirements. Additionally, fertilization cessation increased the proportions of fine colloids(100–450 nm, including nontronite and some amorphous iron oxides) and drove a significant release of iron/aluminum oxide nanoparticles(1–100 nm) and associated P with orthophosphate and pyrophosphate species. In summary, short-term fertilization cessation effectively alleviated soil acidification and inorganic P accumulation, while concomitantly maintaining soil P fertility and improving the potential mobilization of P associated with microparticles.

9,10-Bis(diphenylmethylene)-9,10-dihydroanthracene-based metal-organic assemblies with aggregation-induced emission for multiple sensing

Developing novel emissive supramolecular assemblies with elegant architectures and tunable perfor-mance remains highly desirable yet challenging.Herein,we report the design and synthesis of several 9.10-bis(diphenylmethylene)-9.10-dihydroanthracene-based metal organic assembles with aggregation-induced emission characteristics.Such assemblies feature intriguing thermochromic and mechanochromic properties,ie.,distinguishable fuorescence responses in terms of emission wavelength and intensity un-der variable temperatures and pressures.Moreover,these assemblies can serve as excellent fluorescent sensors for the detection of polysaccharide molecules.Due to the differentiated charge type and den-sity,the assembles display distinct sensing mechanisms toward different polysaccharide molecules.This study provides novel perspectives for the synthesis of buttrfly-like platinum(I)supramolecular coordi-nation complexes with multistimuli-responsiveness for polysaccharide sensing.which will facllitate the development of stimuli-responsive materials.

Cyanostilbene-based near-infrared emissive platinum(Ⅱ) metallacycles for cancer theranostics

In this work,a near-infrared emissive dipyridyl ligand was synthesized and used to prepare three platinum(II)metallacycles with different shapes via metal-coordination-driven self-assembly with different platinum(II)precursors.These metallacycles were further used for both cell imaging and cancer therapy,offering a new type of theranostic agents towards cancer treatment.

Perylene Diimide-Based Multicomponent Metallacages as Photosensitizers for Visible Light-Driven Photocatalytic Oxidation Reaction

Self-assembled supramolecular structures with efficient singlet oxygen(1O2)-generation ability are expected to enable photocatalytic oxidation reactions.Herein,we use two photosensitizers,perylene diimide and benzothiadiazole derivative,as the boards to prepare two barrel-shaped metallacages viametal-coordination-driven self-assembly.