Enhancing the photocatalytic performance of a rutile unit featuring a titanium-oxide cluster by Pb doping.

Titanium-oxide clusters (TOCs) are well-defined molecular models for TiO materials and provide the opportunity to study the structure-activity relationships of TiO. Here, we report a new Pb-doped TOC, Ti12Pb2, which resembles a two-layer decker of the {TiTi} structural units of rutile TiO with two Ti ions replaced by two Pb ions. Its electronic structure, photoresponse, and photocatalytic performances were investigated and compared with those of the Ti14 cluster, which is isostructural to Ti12Pb2.

Reaction-Induced Liquid Crystalline Polybenzoxazine Bearing Aromatic Amide Side Branches.

In this study, a nematic phase structure is incorporated into polybenzoxazine to increase its thermal conductivity. A simple route for the synthesis of a thermally conductive polybenzoxazine containing liquid crystalline (LC) structure by grafting oligomeric p-sulfophenylene-terephthalamide (PSTA) is offered. Benzoxazine monomer of pHBA-da is synthesized via Mannich reaction of p-hydroxy benzoic acid, p-formaldehyde, and dodecyl amine.

Divalent Heterometal Doped Titanium-Oxide Cluster Polymers: Structures, Photoresponse, and Photocatalysis.

Five cluster polymers based on heterometal-doped titanium-oxide cluster (TOC) monomers are reported. The monomers feature Ti-oxide cluster cores and are connected to the divalent closed-shell heterometal anchors by salicylate ligands. The Sr, Ba, and Pb dopants cause the monomers to bind head-to-head and generate linear chains, while the Ca and Cd lead to head-to-tail connections and zigzag chains.

Altitudinal distribution and seasonal migration of asiatic black bear () in kaghan and Siran Valleys, Pakistan.

The Asiatic black bear () is considered one of the largest carnivores inhabiting different territories including coniferous and broad-leaved forests, extending from sea level to the elevation of 4300 m. The Kaghan and Siran Valleys in Pakistan's District Mansehra were the location of the current study. To evaluate the altitudinal distribution and seasonal movement of Asiatic black bears in the region, we used three approaches (sign distribution survey, questionnaire-based survey, and scat collecting).

A butterfly-like lead-doped titanium-oxide compound with high performance in photocatalytic cycloaddition of CO to epoxide.

The cycloaddition reaction of CO to epoxides is quite promising for CO capture and storage as well as the production of value-added fine chemicals. Herein, a novel atomically precise lead-doped titanium-oxide cluster with the formula TiPbO(phen)(Ac)(DMF) (denoted as Ti10Pb2; phen = 1,10-phenanthroline; Ac = acetate; DMF = dimethylformamide) was synthesized through a facile solvothermal process, and is a molecular photocatalyst with surface-anchored main-group metal active sites. Its structure was characterized by single-crystal X-ray diffraction and other complementary techniques.

Lead-Decorated Titanium Oxide Compound with a High Performance in Catalytic CO Insertion to Epoxides.

The CO cycloaddition to epoxides is an efficient method for CO capture and storage, important not only for reducing greenhouse gas emission but also for producing cyclic carbonates, which are valuable industrial materials. In this study, we report a novel high-nuclearity titanium oxide cluster (TOC) inlayed with main-group element Pb, HTiPbO(SA)(DMF)(OH) (denoted as ; SA = salicylate; DMF = ,-dimethylformamide), which has the property of visible-light absorption and has shown high catalytic activities for cycloadditions of CO under visible-light irradiation. The cluster was synthesized in a high yield in a facial solvothermal process.

New picolinate-functionalized titanium-oxide clusters: syntheses, structures and photocatalytic H evolution.

Two nanosized titanium-oxide clusters (TOCs), Ti(μ-O)(μ-O)PA (1; PA = 2-picolinate) and Ti(μ-O)PA (2) were synthesized by using 2-picolinic acid and Ti(OPr) in one-pot reactions. Their structures were determined using single-crystal X-ray diffractometry. Although both have the same core composition of TiO, 1 exhibited superior H evolution activity of up to 180 μmol h g, which is nearly eight times faster than 2.

Cr-Ti Mixed Oxide Molecular Cages: Synthesis, Structure, Photoresponse, and Photocatalytic Properties.

The solvothermal reaction of titanium isopropoxide and chromate in the presence of benzoate produced two novel host-guest clusters encapsulating Cs or HO, and . The most remarkable feature is that the TiO ring is concentrically embraced by a CrO ring to form a rigid host. ESI-MS and Cs NMR revealed that the overall framework structures are preserved, whereas the benzoate ligands on the two clusters may be labile in solutions.

Polyethylene glycol capped copper ferrite porous nanostructured materials for efficient photocatalytic degradation of bromophenol blue.

Three different types (blank, annealed, and functionalized) of copper ferrite nanoparticles (CuFeO) were synthesized by the co-precipitation method. The CuFeO NPs were characterized by Fourier transform infrared (FTIR), Scanning electron microscopy (SEM), X-ray diffraction (XRD), and Energy-dispersive X-ray spectroscopy (EDX) techniques. FTIR analysis confirmed that 3-APTES is successfully grafted on the surface of CuFeO NPs.

Syntheses, structures and ligand binding modes of titanium-oxide complexes of 2-picolinate.

Six titanium-oxide clusters (TOCs) comprised of 6-19 Ti atoms all of which are of nanometer size were synthesized with the functionalization of 2-picolinate (PA). Their structures were determined by single-crystal X-ray diffraction and a few complementary spectroscopic techniques. The binding modes of PA on the surface of the TOCs were analyzed and found to be limited to only one binding mode, that is, PA acts as a bidentate ligand through both pyridyl-N and the carboxylate-O.

A Mesoporous Lead-Doped Titanium Oxide Compound with High Performance and Recyclability in I Uptake and Photocatalysis.

A three-dimensional (3D) mesoporous material with an atomically precise structure, TiPbO(CHCO)(OCH) (), comprised of a novel high-nuclearity Pb-doped titanium oxide cluster (TOC), was synthesized. exhibited a surface area of 45 m g and a pore diameter of 3.5 nm.

Assembly of Interlocked Superstructures with a Titanium Oxide Molecular Ring in Water.

[2]Catenane, [2]rotaxane, and [2]pseudorotaxane based on a cyclic titanium oxide cluster, [TiO(SO)] (), and cyclic/linear alkylammonium cations are reported. Their syntheses, structures, spectroscopy, and stability in water were studied. These molecules were synthesized from and remained intact upon redissolution in acidic water.

Utilization of Biomass Fly Ash for Improving Quality of Organic Dye-Contaminated Water.

Development of innovative methodologies to convert biomass ash into useful materials is essential to sustain the growing use of biomass for energy production. Herein, a simple chemical modification approach is employed to functionalize biomass fly ash (BFA) with 3-aminopropyltriethoxy silane (APTES) to develop an inexpensive and efficient adsorbent for water remediation. The amine-functionalized BFA (BFA-APTES) was fully characterized by employing a range of characterization techniques.

Joint Separable and Non-Separable Transforms for Next-Generation Video Coding.

Throughout the past few decades, the separable Discrete Cosine Transform (DCT), particularly the DCT type II, has been widely used in image and video compression. It is well known that, under first-order stationary Markov conditions, DCT is an efficient approximation of the optimal Karhunen-Loève transform. However, for natural image and video sources, the adaptivity of a single separable transform with fixed core is rather limited for the highly dynamic image statistics, e.

A blind algorithm for reverberation-time estimation using subband decomposition of speech signals.

An algorithm for blind estimation of reverberation time (RT) in speech signals is proposed. Analysis is restricted to the free-decaying regions of the signal, where the reverberation effect dominates, yielding a more accurate RT estimate at a reduced computational cost. A spectral decomposition is performed on the reverberant signal and partial RT estimates are determined in all signal subbands, providing more data to the statistical-analysis stage of the algorithm, which yields the final RT estimate.

No-reference blur assessment of digital pictures based on multifeature classifiers.

In this paper, we address the problem of no-reference quality assessment for digital pictures corrupted with blur. We start with the generation of a large real image database containing pictures taken by human users in a variety of situations, and the conduction of subjective tests to generate the ground truth associated to those images. Based upon this ground truth, we select a number of high quality pictures and artificially degrade them with different intensities of simulated blur (gaussian and linear motion), totalling 6000 simulated blur images.

The African Millennium Villages.

We describe the concept, strategy, and initial results of the Millennium Villages Project and implications regarding sustainability and scalability. Our underlying hypothesis is that the interacting crises of agriculture, health, and infrastructure in rural Africa can be overcome through targeted public-sector investments to raise rural productivity and, thereby, to increased private-sector saving and investments. This is carried out by empowering impoverished communities with science-based interventions.