低温硫化制备ZnS薄膜的物理性质研究

采用磁控溅射方法先在玻璃衬底上室温下沉积Zn金属薄膜，接着先后在200和400 ℃温度下的硫蒸气和氩气流中进行退火，生长出 ZnS 薄膜。薄膜样品的微观结构、物相结构、表面形貌和光学性质分别采用正电子湮没技术 (PAT)、X射线衍射仪 (XRD)、扫描电子显微镜 (SEM)和紫外-可见分光光度计进行表征。该ZnS薄膜在可见光范围具有约80%的高透光率，随着硫化时间的增加，其带隙由3.55 增加到3.57 eV，S/Zn原子比从0.54上升至0.89，薄膜质量明显得到改善，相对于以前报道的真空封装硫化所制备的ZnS薄膜，硫过量问题得到了较好解决。此外，慢正电子湮没多普勒展宽谱对硫化前后薄膜样品中膜层结构缺陷研究表明，硫化后薄膜的S参数明显增大，生成的ZnS 薄膜结构缺陷浓度高于Zn薄膜。     

Metabolomic analysis of raw Pinelliae Rhizoma and its alum‐processed products via UPLC–MS and their cytotoxicity

Alum‐processing is a traditional method to attenuate the toxicity of Pinelliae Rhizoma (tubers of Pinellia ternate, PT). The present study aimed at investigating the chemical and cytotoxic changes during alum processing. Metabolomic profiles of raw and alum‐processed PT were studied based on ultra‐performance liquid chromatography coupled with Orbitrap mass spectrometry. More than 80 chemicals in positive MS mode and 40 chemicals in negative MS mode, such as organic acids, amino acids, glucosides and nucleosides, were identified after multivariate statistical analysis, including principal component analysis and orthogonal partial least‐square discriminant analysis. Almost all of the identified chemical markers were significantly decreased ~10‐ to 100‐fold after alum processing. Meanwhile, the correlations between the chemical markers were assimilated to a positive coefficient from disorderly distribution during the processing. Raw PT extracts could inhibit the proliferation of human carcinoma cells (HCT‐116, HepG2, and A549) at the rate of 40.5, 24.8 and 31.6% more strongly than processed PT. It was concluded that the alum processing of PT could decrease the number of actively water‐soluble principles at the same time as decreasing toxicity. Given the water‐insoluble property of toxic calcium oxalate raphides in PT, we suggest that a more scientific processing method should be sought.     

Regulation of Charge Delocalization in a Heteronuclear Fe2Ru System by a Stepwise Photochromic Process

Heteronuclear complexes FeCp₂?DTE?C?C?Ru(dppe)₂Cl ( 1 o ; dppe=1,2‐bis(diphenylphosphino)ethane, Cp=cyclopentadienyl, DTE=dithienylethene) and FeCp₂?DTE?C?C?Ru(dppe)₂?C?C?DTE?FeCp₂ ( 2 oo ), with redox‐active ferrocenyl and ruthenium centers separated by a photochromic DTE moiety, were prepared to achieve photoswitchable charge delocalization and Fe???Ru electronic communication. Upon UV‐light irradiation of 2 oo , the Fe???Ru heterometallic electronic interaction is increasingly facilitated with stepwise photocyclization, 2 oo → 2 co → 2 cc ; this is ascribed to the gradual increase in π‐conjugated systems. The near‐infrared absorptions in mixed‐valence species [ 2 oo ]⁺/[ 2 co ]⁺/[ 2 cc ]⁺ are gradually intensified following the conversion of [ 2 oo ]⁺→[ 2 co ]⁺→[ 2 cc ]⁺, which demonstrates that the extent of charge delocalization shows progressive enhancement with stepwise photocyclization. As revealed by electrochemical, spectroscopic, and theoretical studies, complex 2 exhibits nine switchable states through stepwise photochromic and reversible redox processes.     

(NH4)Bi2(IO3)2F5: An Unusual Ammonium-Containing Metal Iodate Fluoride Showing Strong Second Harmonic Generation Response and Thermochromic Behavior

An ammonium-containing metal iodate fluoride compound, (NH₄)Bi₂(IO₃)₂F₅, featuring a two-dimensional double-layered framework constructed by [BiO₂F₅]⁶⁻ and [BiO₄F₄]⁹⁻ polyhedra, as well as [IO₃]⁻ groups, was successfully synthesized. The well-ordered alignment of these SHG-active units leads to an extraordinary strong SHG response of 9.2 times that of KDP. Moreover, this compound possesses a large birefringence (Δn=0.0690 at 589.3 nm), a wide energy band gap (E_g=3.88 eV), and a high laser damage threshold (LDT; 40.2×AgGaS₂). In particular, thermochromic behavior was observed for the first time in this type of compound. Such multifunctional crystals will expand the application of nonlinear optical materials.     

Characterizations of ( m,n )-Jordan Derivations and ( m,n )-Jordan Derivable Mappings on Some Algebras

Let R be a ring, M be a R-bimodule and m, n be two fixed nonnegative integers with m + n = 0. An additive mapping δ from R into M is called an(m, n)-Jordan derivation if(m +n)δ(A~2) = 2 mAδ(A) + 2nδ(A)A for every A in R. In this paper, we prove that every(m, n)-Jordan derivation with m = n from a C*-algebra into its Banach bimodule is zero. An additive mappingδ from R into M is called a(m, n)-Jordan derivable mapping at W in R if(m + n)δ(AB + BA) =2mδ(A)B + 2 mδ(B)A + 2 nAδ(B) + 2 nBδ(A) for each A and B in R with AB = BA = W. We prove that if M is a unital A-bimodule with a left(right) separating set generated algebraically by all idempotents in A, then every(m, n)-Jordan derivable mapping at zero from A into M is identical with zero. We also show that if A and B are two unital algebras, M is a faithful unital(A, B)-bimodule and U = [A M N B] is a generalized matrix algebra, then every(m, n)-Jordan derivable mapping at zero from U into itself is equal to zero.     

Bioactive Chemical Constituents of Cercis chinensis

Chemistry of Natural Compounds -