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Chloroplasts are the center of plant life activities including photosynthesis, growth and development, and abiotic stress response. Chloroplast development and biogenesis in rice have been studied in detail, but how does abiotic stress affect chloroplasts is less studied. We obtained an albino mutant, alm1, whose chlorophyll content was greatly decreased. Transmission electron microscopy showed that chloroplast development in alm1 was blocked, especially in thylakoid-like structures, which could not form normally. The ALM1 gene encodes a chloroplast-localized superoxide dismutase. Full-length ALM1 successfully restored the non-albino phenotype, and in knockout lines, the albino phenotype reappeared. The ALM1 gene is expressed mainly in young leaves. alm1 plants died as a consequence of excessive reactive oxygen accumulation after the third-leaf stage. A series of biochemical assays verified that ALM1 interacted with the OsTrxz protein, which is one of the components of plastid-encoded RNA polymerase (PEP) complexes. A western blot experiment indicated that ALM1 played an important role in stabilizing OsTrxz in rice. An overexpression test of ALM1 revealed that ALM1 can increase drought resistance by removing excess reactive oxygen in rice seedlings. This study suggests that ALM1 not only participates in rice chloroplast biogenesis, but also increases rice stress resistance by scavenging excess reactive oxygen.

The morphology of bulliform cells located on the upper epidermis of leaves is one of the most important cell structures affecting leaf shape. Although many mechanisms regulating the development of bulliform cells have been reported, the fine regulatory mechanisms governing this process have rarely been described. To identify novel components regulating rice leaf morphology, a mutant showing a constitutively rolling phenotype from the seedling stage to flowering, known as crm1‐D, was selected for further analysis. Anatomical analyses in crm1‐D were attributable to the size reduction of bulliform cells. The crm1‐D was controlled by a single dominant nuclear gene. Map‐based cloning revealed that Roc8, an HD zipper class IV family member, was responsible for the crm1‐D phenotype. Notably, the 50‐bp sequence in the 3′‐untranslated region (3′‐UTR) of the Roc8 gene represses Roc8 at the translational level. Moreover, the roc8 knockdown lines notably increased the size of bulliform cells. A series of assays revealed that Roc8 negatively regulates the size of bulliform cells. Unexpectedly, Roc8 was also observed to positively mediate lignin biosynthesis without incurring a production penalty. The above results show that Roc8 may have a practical application in cultivating materials with high photosynthetic efficiency and low lignin content.

Leaf angle is one of the most important agronomic traits in rice, and changes in leaf angle can alter plant architecture to affect photosynthetic efficiency and thus determine grain yield. Therefore, it is important to identify key genes controlling leaf angle and elucidate the molecular mechanisms to improve rice yield. We obtained a mutant rela (regulator of leaf angle) with reduced leaf angle in rice by EMS mutagenesis, and map-based cloning revealed that OsRELA encodes a protein of unknown function. Coincidentally, DENSE AND ERECT PANICLE 2 (DEP2) was reported in a previous study with the same gene locus. RNA-seq analysis revealed that OsRELA is involved in regulating the expression of ILI and Expansin family genes. Biochemical and genetic analyses revealed that OsRELA is able to interact with OsLIC, a negative regulator of BR signaling, through its conserved C-terminal domain, which is essential for OsRELA function in rice. The binding of OsRELA can activate the expression of downstream genes repressed by OsLIC, such as OsILI1, a positive regulator of leaf inclination in rice. Therefore, our results suggest that OsRELA can act as a transcriptional regulator and is involved in the regulation of leaf inclination by regulating the transcriptional activity of OsLIC.

Finding diverse and tunable molecular structures is relevant toward the design of functional nanostructures. The photoluminescence of complex [Au2Cl(μ-P-C-κP,κC,κN)]3 (1), featuring a ligand-suppor...

Selective copper(I) to palladium(0) transmetallation of P-donors from the rigid N,N'-diphosphanyl-imidazol-2-ylidene C3 H2 [NP(tBu)2 ]2 (PCNHC P) was observed when known [Cu3 (μ3 -PCNHC P,κP,κCNHC ,κP)2 ](OTf)3 was reacted with [Pd(PPh3 )4 ]. When 1.2 equivalents of [Pd(PPh3 )4 ] was used, the product [Cu2 Pd(μ3 -PCNHC P,κP,κCNHC ,κP)2 ](OTf)2 (2(OTf)2 ) was obtained, which features a CuI -CuI -Pd0 chain and appears to be the first linear heterotrinuclear complex with d10 -d10 interactions between Pd0 and CuI . When the Cu3 precursor was reacted with 3.0 equivalents of [Pd(PPh3 )4 ], the complex [CuPd2 (μ3 -PCNHC P,κP,κCNHC ,κP)2 ](OTf)2 (3(OTf)2 ) was obtained, which, on the basis of magnetic measurements, DFT calculations, and computed nuclear shieldings, was formulated as containing a Pd0 -CuI -Pd0 chain with an electron hole delocalized over the whole cation, including the metal chain. Similarly, selective transmetallation of the P-donors in [Ag3 (μ3 -PCNHC P,κP,κCNHC ,κP)2 ](OTf)3 from silver to palladium (originating from [Pd(PPh3 )4 ]) gave the linear chain [Ag2 Pd(μ3 -PCNHC P,κP,κCNHC ,κP)2 ](OTf)2 (5(OTf)2 ), which on the basis of NMR spectroscopy comprises an AgI -AgI -Pd0 metal core. However, X-ray diffraction data collected on various samples of 5(OTf)2 were modeled with 50:50 metal disorder at the terminal positions, corresponding to a (AgI /Pd0 )-AgI -(AgI /Pd0 ) formulation. Upon standing in solution, 5(OTf)2 transformed to 6(OTf)2 , the regioisomer of 5(OTf)2 in which the Pd center has migrated to the central position of an AgI -Pd0 -AgI chain. Prolonged standing in CH2 Cl2 or by reaction with [PtCl2 (NCMe)2 ] converts complex 6(OTf)2 to the AgI /PdII complex [Ag2 PdCl2 (μ3 -PCNHC P,κP,κCNHC ,κP)2 ](OTf)2 (7(OTf)2 ). The structural data of 2(OTf)2 , 3(OTf)2 , and 7(OTf)2 establish significant heterometallophilic interactions.

Hazel (Corylus spp.) is the most economically important species in the Betulaceae family. Frequent ovary abortion during the prefertilization stage causes the high drop ratio of pistillate flowers and smaller fruit numbers in a fruit cluster, resulting in yield loss. To better understand the mechanism of ovary abortion formation in hazel, we conducted transcriptomic and proteomic analyses and identified genes and proteins that were altered in response to ovary abortion. A total of 89,846 unigenes and 4343 proteins were identified using RNA-seq and iTRAQ technology, respectively. Among them, 1895 unigenes and 710 proteins were differentially expressed and accumulated in the developing and abortive ovary respectively. Furthermore, we employed the Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, revealing pathways that are significantly enriched in both transcriptomic and proteomic assays. These include the phenylalanine metabolic pathway, biosynthesis of phenylpropanoid, biosynthesis of secondary metabolites, and ascorbate and aldarate metabolism. Transcriptome-proteome integrative analysis revealed 42 correlations. Among these, 32 correlations with same changing trend (that are involved in metabolism stress response, vascular strand development, water transport, and seed development) are likely associated with abortive ovary formation. Importantly, ethylene (ETH), jasmonic acid (JA), and salicylic acid (SA) signal transduction pathways may contribute to the regulation of the abortive ovary formation via the up-regulation of ethylene-responsive transcription factor 1 (ERF1/2), jasmonate ZIM domain-containing protein (JAZ), transcription factor MYC2 (MYC2), transcription factor (TGA), and pathogenesis-related protein 1(PR-1). Our work will facilitate the identification of ovary abortion related genes and proteins and provide insights into the molecular mechanism of fruit development.

A mononuclear bis(NHC)/Au(I) (NHC=N-heterocyclic carbene) cationic complex with a rigid bis(phosphane)-functionalized NHC ligand (PC(NHC)P) was used to construct linear Au3 and Ag2 Au arrays, a Au5 cluster with two intersecting crosslike Au3 arrays, and an unprecedented Cu6 complex with two parallel Cu3 arrays. The impact of metallophilic interactions on photoluminescence was studied experimentally.

Selective copper(I) to palladium(0) transmetallation of P-donors from the rigid N,N'-diphosphanyl-imidazol-2-ylidene C

The chromium(II) complexes [CrCl2(t-BuNHC,P-κC)2] (1), [CrCl2(MesNHC,P-κC)2] (2), [CrCl2(DippNHC,P-κC)2] (3), and [CrCl2(P,NHC,P-κC)2] (4) containing the N-phosphanyl- or N,N′-diphosphanyl-substituted N-heterocyclic carbene (NHC) hybrid ligands t-BuNHC,P (1-(di-tert-butylphosphino)-3-tert-butylimidazol-2-ylidene), MesNHC,P (1-(di-tert-butylphosphino)-3-mesitylimidazol-2-ylidene), DippNHC,P (1-(di-tert-butylphosphino)-3-(2,6-diisopropylphenyl)imidazol-2-ylidene), and P,NHC,P (1,3-bis(di-tert-butylphosphino)imidazol-2-ylidene), respectively, were prepared from CrII ([CrCl2(thf)2]) or CrIII ([CrCl3(thf)3] or [Cr(Me)Cl2(thf)3]) precursors. The solid-state structures of these four complexes show square-planar CrII centers, with two trans chloride and two monodentate CNHC donors. Alkylation of 3 and 4 with [Mg(benzyl)2(thf)2] led to the formation of the σ complexes [Cr(benzyl)3(DippNHC,P-κC,κP)] (5) and [Cr(benzyl)3(P,NHC,P-κC,κP)] (6), respectively, with five-coordinate distorted-square-pyramidal CrIII coordin...

Two regioisomeric, non-symmetric P(C2)P(N)-imidazoles, t-Bu2PNCH=CHNC(PPh2) (L1, P(C2) = PPh2, P(N) = P(t-Bu)2) and Ph2PNCH=CHNC[P(t-Bu)2] (L2, P(C2) = P(t-Bu)2, P(N) = PPh2), respectively, show dramatic differences in the reactivity of the N-bound phosphine group; the L2 isomer is extremely sensitive to P-N bond cleavage by nucleophiles, and when coordinated to the PdCl(Me) fragment it undergoes facile interchange of one P(N) phenyl with the methyl originating from Pd.

A series of ion-pair cobalt complexes (C1–C6) supported by (benzimidazolyl)pyridine alcohol ligands ([NNO]) were synthesized and characterized. The single-crystal X-ray diffraction demonstrated that the ion-pair cobalt complexes formed, consisting of [CoL2]2+ and [CoCl4]2−, in which the cobalt center was surrounded by two [NNO] ligands and adopted distorted octahedronal geometry in the cationic moiety along with [CoCl4]2− as the counterion. The type of cocatalyst had a remarkable influence on the catalytic properties and ethylaluminum sesquichloride (EASC) was proved to be the most efficient cocatalyst for the polymerization of 1,3-butadiene to produce high conversion of butadiene and high cis-1,4 content in the resulting polymers. Upon activation with EASC, all the cobalt complexes (C1–C6) displayed high catalytic activity for the polymerization of 1,3-butadiene to yield cis-1,4-polybutadiene with high selectivity (>95%) under the Al/Cat molar ratio of 50 at 30 °C. The conversion of butadiene, microstructure and properties of the resulting polymers were also affected by the reaction parameters and ligand structure.

The heterofunctional and rigid ligand N,N'-diphosphanyl-imidazol-2-ylidene (PCNHCP; P = P(t-Bu)2), through its phosphorus and two N-heterocyclic carbene (NHC) donors, stabilizes trinuclear chain complexes, with either Au3 or AgAu2 cores, and dinuclear Au2 complexes. The two oppositely situated PCNHCP (L) ligands that "sandwich" the metal chain can support linear and rigid structures, as found in the known tricationic Au(I) complex [Au3(μ3-PCNHCP,κP,κCNHC,κP)2](OTf)3 (OTf = CF3SO3; [Au3L2](OTf)3; Chem. Commun. 2014, 50, 103-105) now also obtained by transmetalation from [Ag3(μ3-PCNHCP,κP,κCNHC,κP)2](OTf)3 ([Ag3L2](OTf)3), or in the mixed-metal tricationic [Au2Ag(μ3-PCNHCP,κP,κCNHC,κP)2](OTf)3 ([Au2AgL2](OTf)3). The latter was obtained stepwise by the addition of AgOTf to the digold(I) complex [Au2(μ2-PCNHCP,κP,κCNHC)2](OTf)2 ([Au2L2](OTf)2). The latter contains two dangling P donors and displays fluxional behavior in solution, and the Au···Au separation of 2.8320(6) Å in the solid state is consistent with metallophilic interactions. In the solvento complex [Au3Cl2(tht)(μ3-PCNHCP,κP,κCNHC,κP)](OTf)·MeCN ([Au3Cl2(tht)L](OTf)·MeCN), which contains only one L and one tht ligand (tht = tetrahydrothiophene), the metal chain is bent (148.94(2)°), and the longer Au···Au separation (2.9710(4) Å) is in line with relaxation of the rigidity due to a more "open" structure. Similar features were observed in [Au3Cl2(SMe2)L](OTf)·2MeCN. A detailed study of the emission properties of [Au3L2](OTf)3, [Au3Cl2(tht)L](OTf)·MeCN, [Au2L2](OTf)2, and [Au2AgL2](OTf)3 was performed by means of steady state and time-resolved photophysical techniques. The complex [Au3L2](OTf)3 displays a bright (photoluminescence quantum yield = 80%) and narrow emission band centered at 446 nm with a relatively small Stokes' shift and long-lived excited-state lifetime on the microsecond timescale, both in solution and in the solid state. In line with the very narrow emission profile centered in the violet-blue region, fabrication of organic light-emitting devices (OLEDs) comprising the [Au3L2](OTf)3 complex demonstrated its usefulness as a deep-blue emitter in solution-processed OLEDs. Electrochemical and Raman spectroscopic studies were also performed on [Au3L2](OTf)3. Experimental results were rationalized by means of Wave-Function Theory (WFT) and Density Functional Theory (DFT). MP2 calculations gave a satisfactory description of the structures of the cationic complexes [Au3L2](3+) and [Au2L2](2+) and pointed to Au···Au interactions having an electrostatic component owing to the dissimilar charge distribution in the chain caused by the heterofunctional ligand. The nature of the emitting states and their geometric distortions relative to the ground states in [Au3L2](3+) and [Au2L2](2+) was studied by DFT, revealing contraction of the Au···Au distances and coordination geometry changes by association of the dangling P donor, respectively.

Attempts to evaluate experimentally the donor characteristics of the N,N'-bis(di-tert-butylphosphanyl)-imidazole-2-ylidene (PC(NHC)P) hybrid ligand are described. Thus, reactions of PC(NHC)P with [Rh(μ-Cl)(COD)]2 and [Rh(μ-Cl)(CO)2]2 led to the formation of the mononuclear and dinuclear complexes, [Rh(PC(NHC)P,κP,κC(NHC))2]Cl (PC(NHC)P-RhCl) and [Rh(CO)(PC(NHC),κP,κC(NHC),κN)]2 (PC(NHC)-RhCO), respectively, the latter resulting after in situ cleavage of one (t-Bu)2P-Nimid bond of PC(NHC)P. With ligands acting as a P,C-chelate, a straightforward evaluation of the Tolman electronic parameter (TEP) of the C(NHC) donor is problematical; the viability of dangling P- and bound C(NHC)-donors (i.e.κC(NHC)) has been observed in the trinuclear Fe(ii) chain complex [Fe3Cl2(μ-Cl)4(THF)2(PC(NHC)P,κC(NHC))2] (PC(NHC)P-Fe), obtained by the reaction of PC(NHC)P with [Fe4Cl8(THF)6] and, recently, established on Cr(II), Co(II) and Au(I) centres. Evaluation of the π-accepting properties of the PC(NHC)P (and the related Dipp-PC(NHC)) was based on the (77)Se NMR chemical shifts of the corresponding NHC-Se adducts, PC(NHC)P-Se (and Dipp-PC(NHC)-Se), which were prepared from the free PC(NHC)P (and Dipp-PC(NHC)) and Se. The π-acidity of PC(NHC)P is found to be higher than that of Dipp-PC(NHC) but lower than that of SIPr. The donor ability of the C(NHC) in PC(NHC)P was explored by its reaction with the Lewis acids tris(pentafluorophenyl)borane (B(C6F5)3) and tris(pentafluorophenyl)boroxine ([(C6F5)BO]3), which resulted in stable donor-acceptor adducts with no FLP reactivity. The steric properties of PC(NHC)P and Dipp-PC(NHC) are conformation dependent, with the percent buried volume (%Vbur) of PC(NHC)P in the structurally characterised conformer calculated at 67.6, the largest value currently reported for NHC ligands.

A series of cobalt complexes bearing N-containing diphosphine PNP ligands has been synthesized and characterized. The nature of the ligand structure affects the binding of the ligand to the cobalt center and determines the coordination geometry of the cobalt complexes. All the complexes have been employed to catalyze the polymerization of 1,3-butadiene, in combination with methylaluminoxane (MAO) or ethylaluminum sesquichloride (EASC) as the cocatalyst. Both the nature of the ligand and the type of cocatalyst had a remarkable influence on the polymerization activity, microstructure and molecular weight of the resulting polymers. The [Co]/MAO catalytic systems resulted in relatively lower conversions of butadiene and cis-1,4 contents in the polymers than the corresponding [Co]/EASC catalytic systems. Upon activation with EASC, the polymerization behaviors of the catalytic systems were also affected by the reaction parameters.

A series of mono- and di-nuclear nickel(II) complexes bearing 3-aryliminomethyl-2-hydroxybenzaldehyde ligands were synthesized and characterized by FT-IR and elemental analysis along with single-crystal X-ray diffraction. The X-ray diffraction analysis revealed that the dinuclear nickel complexes formed with two bridged ligands and one bromide around each nickel center and the mononuclear nickel complexes bearing two centrosymmetrical ligands exhibited a distorted square-planar geometry. Upon activation with methylaluminoxane (MAO), all these nickel complexes displayed high catalytic activities up to 9.88 × 107 g(PNB) mol−1(Ni) h−1 (6b) for the vinyl polymerization of norbornene, yielding the vinyl-type PNBs with high molecular weights and narrow molecular weight distributions. The steric and electronic factors of ligands and reaction parameters had influences on the catalytic properties.

A series of nickel and palladium complexes bearing (imino)pyridyl alcohol tridentate [N,N,O] ligands, 2-(ArN CMe)-6-{(HO)CR2}C5H3N (L1–L4), were synthesized and sufficiently characterized by elemental and spectroscopic analysis along with X-ray diffraction analysis. The X-ray diffraction demonstrated that five-coordinated nickel halide complexes (1a–4a and 1b) and six-coordinated nickel acetate complex (1c) were prepared, and cationic palladium complexes (1d and 2d) formed with the [PdCl4]2− counterion. All these complexes displayed high catalytic activities up to 1.883 × 107 g(PNB) mol−1(cat) h−1 (2d) for the vinyl polymerization of norbornene on treatment with excess methylaluminoxane (MAO), affording the vinyl-type PNBs with high molecular weights and relatively narrow molecular weight distributions. The parameters of reaction conditions, the type of metals and steric effects of coordinative ligands had influences on the catalytic properties.

Poly (amido-amine) (PAMAM) as one of the earliest synthesized dendrimers is now widely used in biomedicine, host–guest chemistry and so on. PAMAM dendrimers from generation 2 to 6 were studied by all-atom molecular dynamic simulations using different force fields and different coarse-graining schemes. The DREIDING force field is found to provide the best accuracy in predicting the structures and properties of PAMAM dendritic molecules. Simulation with the coarse-grained approach decreases the considerable CPU-time cost while keeping commensurate accuracy with all-atom simulations under the same simulation condition. The radius of gyration, solvent accessible surface area, solvent accessible volume and fractal dimension are calculated as functions of generation. Results show that PAMAM dendrimers have a fractal structure with dimensions between 2.0 and 3.0. The ample external terminal groups and internal voids make the PAMAM dendrimer an excellent candidate for drug carriers. The terminal groups of PAMAM dendrimers are sufficiently flexible to interpenetrate almost the whole molecule. The simulation results on different coarse-grained models are compared; the coarse-graining scheme has significant influence on the simulation accuracy.

We report an effective method to synthesize a red long-lasting phosphorescent material, Y 2 O 2 S: Eu 3+ , Mg 2+ , Ti 4+ nanotubes. Y(OH) 3 nanotubes were first synthesized by a convenient hydrothermal method to serve as the precursor. Y 2 O 2 S: Eu 3+ , Mg 2+ , Ti 4+ powders were obtained with high yield and purity by calcinating the precursor in CS 2 atmosphere. The morphology and optical properties of the composites were characterized. XRD investigation showed a pure phase of Y 2 O 2 S. SEM and TEM observation revealed that the phosphors with diameters of 100–200 nm and lengths of 1–3 μm inherited the tube-like shape from the precursor after being calcinated in CS 2 atmosphere. From the spectrum, the main emission peaks are ascribed to Eu 3+ ions transition from 5 D J ( J =0, 1, 2) to 7 F J ( J =0, 1, 2, 3, 4). After irradiation by 265 or 325 nm, the phosphor emitted red color long-lasting phosphorescence. It was considered that the red-emitting long-lasting phosphorescence was due to the persistent energy transfer from the traps to the Ti 4+ and Mg 2+ ions.

A high-brightness Eu2+ and Dy3+ co-doped strontium aluminate-based transparent surface-crystallized long-lasting phosphorescent (LLP) glass-ceramic was synthesized using solid-state sintering method in CO atmosphere. The crystal structure, morphology and optical properties of the composite were characterized. By the X-ray diffraction diffusion (XRD) data, SrAl2O4 was demonstrated to be the crystallite in the glass-ceramic. The TEM photographs indicated that the sample had a universal small crystallite size about 10–20 nm on its surface. The SrAl2O4:Eu2+, Dy3+ crystallites were produced during the quenching process. After irradiated with ultraviolet (UV) light, the glass-ceramic emitted green long-lasting phosphorescence with an excitation peak at 375 nm and emission peak at 520 nm ascribed to the characteristic 5d–4f transition of Eu2+. Both the PL spectra and luminance decay revealed that this phosphor had efficient luminescence and long-lasting properties. By comparing with the heat-treated sample, the obtained transparent surface-crystallized LLP glass-ceramic puts up higher transparency and long phosphorescence, and could be obtained more easily.

Y2O2S:Eu3+, Mg2+, Ti4+ nanorods were prepared by a solvothermal procedure. Rod-like Y(OH)3 was firstly synthesized by hydrothermal method to serve as the precursor. Y2O2S:Eu3+, Mg2+, Ti4+ powders were obtained by calcinating the precursor at CS2 atmosphere. The Y2O2S:Eu3+, Mg2+, Ti4+ phosphor with diameters of 30–50 nm and lengths up to 200–400 nm inherited the rod-like shape from the precursor after calcined at CS2 atmosphere. The Y2O2S:Eu3+, Mg2+, Ti4+ nanorods showed hexagonal pure phase, good dispersion and exhibited bright red luminescence. After irradiation by 265 or 325 nm for 5 min, the phosphor emitted red long-lasting phosphorescence, and the phosphorescence could be seen with the naked eyes in the dark clearly for more than 1 h after the irradiation source was removed. It was considered that the long-lasting phosphorescence was due to the persistent energy transfer from the traps to the Ti4+ and Mg2+ ions to generate the red-emitting long-lasting phosphorescence.

The products of the reaction between N,N'-diphosphanylimidazol-2-ylidene (P-C-P) and gold(I) precursors depend on the nature of the anions associated with the latter. In contrast to the reported reaction with [Au(tht)2(OTf)], the use of [AuCl(tht)] led to the new hexanuclear complex 1, which features a Au6(μ3-P-C,κC,κN,κP)3 skeleton. The reaction of lithium imidazolide (P-C-Li) and [AuCl(tht)] also afforded 1, together with an unusual salt of the general formula [Au5Cl(μ3-P-C-κP,κC,κN)3]2[AuCl2]2 (2), which contains [Au5(μ3-P-C-κP,κC,κN)](+) subunits. In the solid state, one of these Au5 cations is associated with an [AuCl2](-) anion, while two other cations interact through their unique dicoordinated N-Au-N center with a [AuCl2](-) anion, with the charge of the resulting monocation being compensated for by another [AuCl2](-) anion to give a Au12 salt. Remarkably, the latter displays seven different bonding types at Au(I): C-Au-C, N-Au-N, P-Au-P, Cl-Au-Cl, C-Au-N, P-Au-Cl, and Au···Au.

A novel N,N'-diphosphanyl-imidazol-2-ylidene acts as a stable, hybrid PC(NHC)P ligand for M2 or linear M3 (M = Cu, Ag, Au) arrays with metallophilic interactions.

Nanocrystalline SrAl2Si2 O8 :Eu2+ phosphor layers were coated on nonaggregated, monodisperse and spherical SiO2 particles using a hydrothermal homogeneous precipitation. After annealing at 1100 °C, core-shell SiO2@SrAl2 Si2 O8 :Eu2+ particles were obtained. They were characterized with x-ray diffraction (XRD), scanning electron microscopy, transmission electron microscopy and photoluminescence techniques. XRD analysis confirmed the formation of SiO2 @SrAl2 Si2 O8 :Eu2+ particles; it indicated that the SrAl2 Si2 O8 :Eu2+ shells on SiO2 particles consisted of hexagonal crystallites. The core-shell phosphors obtained are well-dispersed submicron spherical particles with a narrow size distribution. The thickness of the coated layer is approximately 20–40 nm. Under ultraviolet excitation (361 nm), the particles emit blue light at about 440 nm due to the Eu2+ ions in their shells.

Nanocrystalline SrAl2Si2O8 :Eu2+ phosphor layers were coated on nonaggregated, monodisperse and spherical SiO2 particles using a hydrothermal homogeneous precipitation. After annealing at 1100 °C, core-shell SiO2@SrAl2Si2O8 :Eu2+ particles were obtained. They were characterized with x-ray diffraction (XRD), scanning electron microscopy, transmission electron microscopy and photoluminescence techniques. XRD analysis confirmed the formation of SiO2 @SrAl2Si2O8 :Eu2+ particles; it indicated that the SrAl2Si2O8 :Eu2+ shells on SiO2 particles consisted of hexagonal crystallites. The core-shell phosphors obtained are well-dispersed submicron spherical particles with a narrow size distribution. The thickness of the coated layer is approximately 20–40 nm. Under ultraviolet excitation (361 nm), the particles emit blue light at about 440 nm due to the Eu2+ ions in their shells.

A series of cobalt(II) complexes bearing 3-aryliminomethyl-2-hydroxybenzaldehydes (tridentate [NOO] ligands) was prepared and characterized by FT-IR and elemental analysis along with single-crystal X-ray diffraction. The X-ray diffraction analysis revealed that a dinuclear centrosymmetrical structure formed, in which each cobalt atom is surrounded by two bridged ligands and two acetate groups as a distorted octahedron. These dinuclear cobalt complexes displayed high catalytic activities for the polymerization of 1,3-butdiene on activation with organoaluminum cocatalysts to yield cis-1,4-polybutadiene with high selectivity. Ethylaluminum sesquichloride (EASC) was found to be the most efficient cocatalyst resulting in high conversion of butadiene and cis-1,4 content in the polymers with moderate molecular weight. The high catalytic activity and stereoselectivity could be achieved in a wide range of reaction conditions. All the dinuclear cobalt complexes (C1–C6) yielded predominantly cis-1,4-polybutadienes (> 96%) with negligible amounts of trans-1,4 (< 2.4%) and 1,2-vinyl (< 1.5%) products under the Al/Co molar ratio of 80 at 25 °C. The ligand modification by varying the substituents at the 4-position of phenol and on the imino-N aryl ring showed slight influence on the catalytic activity and microstructure of the resulting polymers.

Nanocrystalline SrAl2Si2 O8 :Eu2+ phosphor layers were coated on nonaggregated, monodisperse and spherical SiO2 particles using a hydrothermal homogeneous precipitation. After annealing at 1100??C, core-shell SiO2@SrAl2 Si2 O8 :Eu2+ particles were obtained. They were characterized with x-ray diffraction (XRD), scanning electron microscopy, transmission electron microscopy and photoluminescence techniques. XRD analysis confirmed the formation of SiO2 @SrAl2 Si2 O8 :Eu2+ particles; it indicated that the SrAl2 Si2 O8 :Eu2+ shells on SiO2 particles consisted of hexagonal crystallites. The core-shell phosphors obtained are well-dispersed submicron spherical particles with a narrow size distribution. The thickness of the coated layer is approximately 20?40?nm. Under ultraviolet excitation (361?nm), the particles emit blue light at about 440?nm due to the Eu2+ ions in their shells.

A phosphorescent material in the form of Y2O2S:Eu3+, Mg2+, Ti4+ hollow microspheres was prepared by homogeneous precipitation using monodispersed carbon spheres as hard templates. Y2O3:Eu3+ hollow microspheres were first synthesized to serve as the precursor. Y2O2S:Eu3+, Mg2+, Ti4+ powders were obtained by calcinating the precursor in a CS2 atmosphere. The crystal structure, morphology and optical properties of the composites were characterized. X-ray diffraction measurements confirmed the purity of the Y2O2S phase. Electron microscopy observations revealed that the Y2O2S:Eu3+, Mg2+, Ti4+ particles inherited the hollow spherical shape from the precursor after being calcined in a CS2 atmosphere and that they had a diameter of 350–450 nm and a wall thickness of about 50–80 nm. After ultraviolet radiation at 265 or 325 nm for 5 min, the particles emitted strong red long-lifetime phosphorescence originating from Eu3+ ions. This phosphorescence is associated with the trapping of charge carriers by Ti4+ and Mg2+ ions.