Water photolysis. Part 2. An investigation of the relative advantages of various components of the sensitiser–electron relay–metal colloid system for the photoproduction of hydrogen from water, and the use of these systems in the photohydrogenation of unsaturated organic substrates

Author(s):  
Chee-Kai Tan ◽  
Vincent Newberry ◽  
Thomas R. Webb ◽  
Charles A. McAuliffe
2007 ◽  
Vol 544-545 ◽  
pp. 801-804 ◽  
Author(s):  
Masanori Tomonari ◽  
Kohsuke Mori ◽  
Hiromi Yamashita

For the synthesis of the nano-sized Ag metal particle, the sodium borohydride for the reducing agent was added into the aqueous solution of the AgNO3 with 3-mercapto-propionic acid as protective agent. Because the surface of nano-sized Ag metal particle was protected by the adsorbed 3-mercapto-propionic acid, the synthesis of the aqueous colloid system with high density became possible. The negative charge of carboxylate anion protect the aggregation of metal particles in the solution of high pH value (pH > 5), but the aggregation was occurred in the solution of low pH value (pH < 2). By changing the quantity of the agent of propionic acid and the pH value of solution, the particle size can be controlled optionally in the range of 50~200 nm.


Author(s):  
Douglas L. Dorset

A variety of linear chain materials exist as polydisperse systems which are difficultly purified. The stability of continuous binary solid solutions assume that the Gibbs free energy of the solution is lower than that of either crystal component, a condition which includes such factors as relative molecular sizes and shapes and perhaps the symmetry of the pure component crystal structures.Although extensive studies of n-alkane miscibility have been carried out via powder X-ray diffraction of bulk samples we have begun to examine binary systems as single crystals, taking advantage of the well-known enhanced scattering cross section of matter for electrons and also the favorable projection of a paraffin crystal structure posited by epitaxial crystallization of such samples on organic substrates such as benzoic acid.


2003 ◽  
Vol 769 ◽  
Author(s):  
C. K. Liu ◽  
P. L. Cheng ◽  
S. Y. Y. Leung ◽  
T. W. Law ◽  
D. C. C. Lam

AbstractCapacitors, resistors and inductors are surface mounted components on circuit boards, which occupy up to 70% of the circuit board area. For selected applications, these passives are packaged inside green ceramic tape substrates and sintered at temperatures over 700°C in a co-fired process. These high temperature processes are incompatible with organic substrates, and low temperature processes are needed if passives are to be embedded into organic substrates. A new high permeability dual-phase Nickel Zinc Ferrite (DP NZF) core fabricated using a low temperature sol-gel route was developed for use in embedded inductors in organic substrates. Crystalline NZF powder was added to the sol-gel precursor of NZF. The solution was deposited onto the substrates as thin films and heat-treated at different temperatures. The changes in the microstructures were characterized using XRD and SEM. Results showed that addition of NZF powder induced low temperature transformation of the sol-gel NZF phase to high permeability phase at 250°C, which is approximately 350°C lower than transformation temperature for pure NZF sol gel films. Electrical measurements of DP NZF cored two-layered spiral inductors indicated that the inductance increased by three times compared to inductors without the DP NZF cores. From microstructural observations, the increase is correlated with the changes in microstructural connectivity of the powder phase.


2013 ◽  
Vol 19 (1) ◽  
pp. 28
Author(s):  
Hamda Situmorang ◽  
Manihar Situmorang

Abstract Implementation of demonstration method in the teaching of chemistry is assigned as the right strategy to improve students’ achievement as it is proved that the method can bring an abstract concept to reality in the class. The study is conducted to vocational high school students in SMKN1 Pargetteng getteng Sengkut Pakfak Barat at accademic year 2013. The teaching has been carried out three cycles on the teaching of chemistry topic of colloid system. In the study, the class is divided into two class, experiment class and control class. The demontration method is used to teach students in experimental class while the teaching in control class is conducted with lecture method. Both are evaluated by using multiple choise tests before and after the teaching procedures, and the ability of students to answer the problems are assigned as students’ achievements. The results showed that demonstration method improved students’ achievement in chemistry. The students in experimental class who are taughed with demonstration method (M=19.08±0.74) have higher achievements compare with control class (M=12.91±2.52), and both are significantly different (tcalculation 22.85 > ttable 1.66). The effectivity of demostration method in experimental class (97%) is found higer compare to conventional method in control class (91%).


2018 ◽  
Author(s):  
Fei He ◽  
Li Mi ◽  
Yanfei Shen ◽  
Toshiyuki Mori ◽  
Songqin Liu ◽  
...  

Developing highly efficient artificial enzymes that directly employ O<sub>2</sub> as terminal oxidant has long been pursued but has rarely achieved yet. We report Fe-N-C has unusual enzyme-like activity in both dehydrogenation and monoxygenation of organic substrates with ~100% selectivity by direct using O<sub>2</sub>.


2018 ◽  
Vol 2 (95) ◽  
pp. 78-81
Author(s):  
L.I. Shkarivska

The changes of the soil’s humus soil within the rural areas are investigated for the organic farming system. The most significant impact of organic agriculture on humus content over 55% was observed on soddy podzolic soils (V>75%), the lowest –7,5% on typical chernozem (V≈16%). Changes in the qualitative composition of humus for the introduction of various types of organic substrates are analyzed.


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