PENGARUH PENAMBAHAN TANAMAN BERUAS LAUT (Scaevola taccada) DALAM PEMBUATAN BIOPLASTIK DARI Kappaphycus alvarezii

The manufacture of bioplastics from kappapycus alvarezii with the addition of extraction of the plant clade, the sea (Scaevola taccada). This study examines the influence of the addition of extracts of the plant clade, the sea and the concentration of carrageenan on physical and mechanical characteristics of bioplastics.The variables studied is the addition of the amount of carrageenan 2 g, 1.5 g, and 1 g with plant extracts clade, sea 0%, 2.5% and 5%. The results obtained from the manufacture of bioplastics to the thickness of the highest in treatment F1, namely 0.393 mm, for all the thickness of the average range 0.0320-0.393 mm. The level of solubility of the most high are in treatment F1 that is 20,92 minutes, for an average of all the solubility range 12.59-20.92 minutes. The rejection and death of the insects was highest in treatment F3, 7% and 3% with the addition of a leaf segmented sea (Scaevola teccada). Thus the addition of the clade, the sea can be said to not meet the Japanesse Industrial Standard (JIS) in the determination of the thickness of the bioplastic that is good that is equal to ≤ 0.25 mm and also for solubility do not meet the SNI to the water resistance of 99%.

Unveiling the Defect Structure of Lithium Niobate with Nuclear Methods

X-ray and neutron diffraction studies succeeded in the 1960s to determine the principal structural properties of congruent lithium niobate. However, the nature of the intrinsic defects related to the non-stoichiometry of this material remained an object of controversial discussion. In addition, the incorporation mechanism for dopants in the crystal lattice, showing a solubility range from about 0.1 mol % for rare earths to 9 mol % for some elements (e.g., Ti and Mg), stayed unresolved. Various different models for the formation of these defect structures were developed and required experimental verification. In this paper, we review the outstanding role of nuclear physics based methods in the process of unveiling the kind of intrinsic defects formed in congruent lithium niobate and the rules governing the incorporation of dopants. Complementary results in the isostructural compound lithium tantalate are reviewed for the case of the ferroelectric-paraelectric phase transition. We focus especially on the use of ion beam analysis under channeling conditions for the direct determination of dopant lattice sites and intrinsic defects and on Perturbed Angular Correlation measurements probing the local environment of dopants in the host lattice yielding independent and complementary information.

Phase Boundary Mapping in ZrNiSn Half-Heusler for Enhanced Thermoelectric Performance

The solubility range of interstitial Ni in the ZrNi1+xSn half-Heusler phase is a controversial issue, but it has an impact on the thermoelectric properties. In this study, two isothermal section phase diagrams of the Zr-Ni-Sn ternary system at 973 K and 1173 K were experimentally constructed based on the binary phase diagrams of Zr-Ni, Zr-Sn, and Ni-Sn. The thermodynamic equilibrium phases were obtained after a long time of heating treatment on the raw alloys prepared by levitation melting. Solubilities of x<0.07 at 973 K and x<0.13 at 1173 K were clearly indicated. An intermediate-Heusler phase with a partly filled Ni void was observed, which is believed to be beneficial to the lowered lattice thermal conductivity. The highest ZT value~0.71 at 973 K was obtained for ZrNi1.11Sn1.04. The phase boundary mapping provides an important instruction for the further optimization of ZrNiSn-based materials and other systems.

Inflexible stoichiometry in bulk pyrite FeS2 as viewed by in situ and high-resolution X-ray diffraction

Non-stoichiometry is considered to be one of the main problems limiting iron pyrite, FeS2, as a photovoltaic absorber material. Although some historical diffraction experiments have implied a large solubility range of FeS2−δ with δ up to 0.25, the current consensus based on calculated formation energies of intrinsic defects has lent support to line-compound behavior. Here it is shown that pyrite stoichiometry is relatively inflexible in both reductive conditions and in autogenous sulfur partial pressure, which produces samples with precise stoichiometry of FeS2 even at different Fe/S ratios. By properly standardizing in situ gas-flow X-ray diffraction measurements, no significant changes in the lattice parameter of FeS2 can be resolved, which portrays iron pyrite as prone to forming sulfur-deficient compounds, but not intrinsic defects in the manner of NiS2−δ.

Bone Degreasing – Finding a New Solution to an Old Problem

The South Australian Museum boasts the largest and most comprehensive cetacean collection in Australia, including various large cetacean skeletons. The preparation of these skeletons was done at various locations throughout the history of the Museum until the state government funded a purpose-built preparation facility which opened in 1983. The well-equipped centre was fitted with a large (2800 L) custom-built liquid-vapour degreaser that used trichloroethylene (TCE) as solvent. Many beautifully degreased skeletons, including a 22 m pygmy blue whale, were prepared during its 15-year operation. An accidental spill of TCE in 1999 led to the decommissioning of the unit. The decision to abandon the use of the toxic and dangerous TCE has led to a series of experiments to find a benign replacement process that will work either with the existing degreaser or heated maceration vats. Numerous chemicals and treatment methods have been trialled with limited success. However, one particular group of chemicals, glycol ether surfactant compounds, has shown promise and has been the main focus for our ongoing studies. Glycol ethers are broad-spectrum active solvents characterised by high dilution ratios, low evaporation rates and wide solubility range. Their unique solubility characteristics also allow them to be used as a coupling solvent in more complex situations containing both hydrophilic and hydrophobic components, and because of their compatibility with non-ionic surfactants, blended formulations with glycol ether solvents may provide a new solution to an old problem.

All-Inorganic and Hybrid Capping of Nanocrystals as Key to Their Application-Relevant Processing

The design of the surface chemistry of colloidal semiconductor nanocrystals (NCs) presents a powerful synthetic approach that allows to tune the optical and electronic properties of the particles in independent and precisely desired manner, to provide chemical and colloidal stability in diverse media, and, finally, to control their targeted applicability ranging from catalysis, medicine to advanced electronic devices. In this article, we summarize the successful functionalization of colloidal NCs with specifically chosen ligands using a novel ligand-exchange strategy. To transform diverse colloidal NCs into a competitive class of solution-processed semiconductors for electronic applications, we replaced the pristine, insulating ligands with tiny inorganic and hybrid inorganic/organic species. The surface modification with inorganic ions modulates the charge carrier density in NC units and guarantees enhanced interparticle interactions. The subsequent functionalization of the all-inorganic-capped NCs with organic molecules leads to the formation of hybrid inorganic/organic-capped NCs. For example, the introduction of short amine molecules enables to preserve the optical and electronic characteristics of their all-inorganic counterparts, while extending the solubility range and improving the ability to form long-range ordered 2D and 3D superstructures. Moreover, these short amines can be further used as convenient axillary co-ligands facilitating the surface functionalization of all-inorganic NCs with other biocompatible molecules, such as polyethylene glycol (PEG). This opens further perspectives for NCs not only in optoelectronic but also in biological and medical applications.