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71.
We describe a novel titanium phthalocyanine that shows no aggregation when anchored to nanocrystalline TiO2 films through its axial carboxylated ligand without the use of co-adsorbents; state selective electron injection into the TiO2 is demonstrated, resulting in efficient photocurrent generation in dye sensitised photoelectrochemical solar cells.  相似文献   
72.
Summary The metal ion content of heavy metal soaps can be successfully determined colorimetrically using their dilute solutions in pyridine. Measurements with copper and nickel soaps (myristates and palmitates) could be carried out at 675 and 650 nm respectively, those for the corresponding cobalt soaps (myristate and palmitate) at 550 nm.
Zusammenfassung Der Metallgehalt von Schwermetallseifen kann mit gutem Erfolg colorimetrisch bestimmt werden, wenn man die verdünnte Lösung der Substanz in Pyridin verwendet. Messungen an Kupfer- und Nickelseifen (Myristate und Palmitate) wurden bei 675 bzw. 650 nm, an Kobaltseifen (ebenfalls Myristat und Palmitat) bei 550 nm durchgeführt.


Thanks are due to Prof. A. R. Kidwai for providing facilities and to the Council of Scientific and Industrial Research, India for the award of a fellowship to one of us (R. H.) to carry out this work.  相似文献   
73.
As a rapidly growing vast country, there is need in Nigeria to develop alternative energy sources to meet its ever increasing energy demands. Tar sands apart from its popular use as a source of asphaltic material for road surfacing is a new energy raw material in Nigeria. The immense industrial applications and utilization of the by-products of tar sands provide great incentives for its development. PIGE and PIXE techniques were employed for the determination of the major, minor and trace elemental concentrations in Nigerian tar sands including sulfur which occurs as pyrites, organic sulfur and sulfates. Proton beams produced by the 7 MV CN and 2.5 MV AN 200 Van de Graaff accelerators at I.N.F.N. Laboratori Nazionali di Legnaro (LNL) at Padova, Italy, were used for the PIGE and PIXE analysis, respectively. Results of this novel study are presented, discussed, and compared with some data from previous worker and values from Athabasca (Canada).  相似文献   
74.
Photo-redox mediated ring-opening metathesis polymerization (photo-ROMP) is an emerging ROMP technique that uses an organic redox mediator and a vinyl ether initiator, in contrast to metal-based initiators traditionally used in ROMP. The reversibility of the redox-mediated initiation and propagation steps enable spatiotemporal control over the polymerization. Herein, we explore a simple, inexpensive means of controlling molecular weight, using alpha olefins as chain transfer agents. This method enables access to low molecular weight oligomers, and molecular weights between 1 and 30 kDa can be targeted simply by altering the stoichiometry of the reaction. This method of molecular weight control was then used to synthesize a functionalized norbornene copolymer in a range of molecular weights for specific materials applications.  相似文献   
75.
Journal of Applied Spectroscopy - Amitriptyline hydrochloride (AMH) is a first-generation tricyclic antidepressant drug. Higher doses of AMH may lead to undesirable clinical conditions such as...  相似文献   
76.
Journal of Heuristics - Motivated by the celebrated paper of Hooker (J Heuristics 1(1): 33–42, 1995) published in the first issue of this journal, and by the relative lack of progress of both...  相似文献   
77.
Journal of Solid State Electrochemistry - In this report, the effects of photoactive blend compositions, film thicknesses, and annealing conditions on the P3HT:PC70BM solar cells performance and...  相似文献   
78.
Poor dispersion characteristics of rockets, due to the orientation of the launcher for multiple launch rocket system (MLRS) departing from that intended, have always restricted the MLRS development for several decades. Orienting control is a key technique to improve the dispersion characteristics of rockets. The purpose of this paper is to propose an orienting control method for launcher of the MLRS in a salvo firing. Because the MLRS is a typical nonlinear system, the major difficulty in designing the orienting controller lies in the nonlinearity. To deal with the nonlinearity, the concept of computed torque control is introduced. The MLRS equation of motion is established using Lagrange method. The inner loop feedforward and the outer loop feedback are adopted to design the controllers for the azimuth and elevation axes of MLRS. By combining the inner and outer control loops together, the PID-computed torque controller is designed. The numerical simulation is implemented to show the control performance, and then, the effectiveness and applicability of the proposed controller are demonstrated by the firing experiment of a salvo of three rockets.  相似文献   
79.
The construction industry is one of the largest sectors in the US economy, yet little is known about the key macroeconomic parameters that affect its industry’s structure and performance. The main objectives of this research are (1) to analyse the macroeconomic performance of construction industry as a whole and at 14 of its sub-sectors in terms of labour productivity, gross margin, and worker's wages; and (2) to develop a quantitative model that predicts a firm's profitability by analysing various levels of labour productivity. The results of a non-linear regression analysis based on the comprehensive US Economic Census data show that the construction industry’s sub-sectors with the highest productivity are the most profitable with regard to the gross margins that they are able to generate. This study and its model will help decision makers better assess macroeconomic performance and conduct trend analysis of the construction industry to serve as a basis for developing strategic roadmap for the future.  相似文献   
80.
We herein report an amphiphilic polymer‐, carboxylated multiwalled carbon nanotube (CNT)‐, silane polymer‐, and streptavidin‐modified indium tin oxide (ITO) electrode that allows low nonspecific binding and efficient immobilization of DNA, along with good electrocatalytic activities and low background‐current levels. The low nonspecific binding results from the well‐covering of the CNT and ITO surface with the amphiphilic polymer and silane polymer, as well as the poly(ethylene glycol) groups of the polymers. The streptavidin for DNA immobilization is covalently attached to the carboxylic acid groups of the amphiphilic polymer and CNT. A low surface coverage of CNT on the ITO electrode provides the good electrocatalytic activities and low background‐current levels. The fabricated electrode enables us to achieve a detection limit of 100 pM in DNA detection.  相似文献   
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