Recent studies chemical sensors based on phthalocyanines

2009 ◽  
Vol 13 (11) ◽  
pp. 1179-1187 ◽  
Author(s):  
Zafer Ziya Öztürk ◽  
Necmettin Kılınç ◽  
Devrim Atilla ◽  
Ayşe Gül Gürek ◽  
Vefa Ahsen
Keyword(s):  
Liquid Crystalline ◽  
Chemical Properties ◽  
Sensing Properties ◽  
Sensor Performance ◽  
Chemical Recognition ◽  
Linear Sorption ◽  
Sorption Energy ◽  
Physical And Chemical ◽  
Gas Response ◽  
Good Agreement

Phthalocyanines (Pcs) are organic compounds able to act as chemical recognition systems because of the various physical effects induced in them by interaction with a large number of gases. The gas response, stability and other sensing characteristics of the Pc films are affected by many factors, such as film morphology, molecular orientation and so on. The interaction between the Pc coatings and the gas molecules may be classified in terms of irreversible chemical affinity, reversible (usually charge transfer) chemical reaction or sorption. The nature of the interactions between the coating and vapor molecules determines the selectivity, sensitivity, signal kinetics, and the reversibility of the sensor. The magnitude of these interactions may be conveniently described in the frame of the linear sorption energy relationship (LSER) model that has been shown to be very efficient at predicting the behavior of polymer-based sensors. In this paper, the effect of coating parameters on sensing properties and sensing mechanism are reviewed. We have proposed an alternative way to achieve optimal sensor performance: liquid crystalline Pcs forming self-ordered thin films of defined area and thickness simply by heating the sample over the phase transition temperature and synthetized mesomorphic and functionalized phthalocyanines, to develop sensors based on mass-sensitive transducers (quartz crystal microbalance, QCM). Phthalocyanines used are discussed in terms of their physical and chemical properties, as well as their sensing properties: sensitivity, selectivity and reversibility. We showed our results with LSER and the results are in good agreement with this theory.

scholarly journals From nanoscopic to macroscopic photo-driven motion in azobenzene-containing materials

Nanophotonics ◽  
2018 ◽  
Vol 7 (8) ◽  
pp. 1387-1422 ◽  
Author(s):  
Stefano L. Oscurato ◽  
Marcella Salvatore ◽  
Pasqualino Maddalena ◽  
Antonio Ambrosio
Keyword(s):  
Liquid Crystalline ◽  
Large Scale ◽  
Surface Engineering ◽  
Spatial Scales ◽  
Chemical Properties ◽  
Glassy Materials ◽  
Uv Visible ◽  
Physical And Chemical ◽  
And Robotics ◽  
And Chemical Properties

AbstractThe illumination of azobenzene molecules with UV/visible light efficiently converts the molecules between trans and cis isomerization states. Isomerization is accompanied by a large photo-induced molecular motion, which is able to significantly affect the physical and chemical properties of the materials in which they are incorporated. In some material systems, the nanoscopic structural movement of the isomerizing azobenzene molecules can be even propagated at macroscopic spatial scales. Reversible large-scale superficial photo-patterning and mechanical photo-actuation are efficiently achieved in azobenzene-containing glassy materials and liquid crystalline elastomers, respectively. This review covers several aspects related to the phenomenology and the applications of the light-driven macroscopic effects observed in these two classes of azomaterials, highlighting many of the possibilities they offer in different fields of science, like photonics, biology, surface engineering and robotics.

High Sensitivity Humidity Sensor Based on ZnSnO3 Composite Nanocube

2013 ◽  
Vol 594-595 ◽  
pp. 872-876
Author(s):  
N.D. Md Sin ◽  
M.Z. Musa ◽  
M.H. Mamat ◽  
S. Ahmad ◽  
A. Abdul Aziz ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Humidity Sensor ◽  
Chemical Properties ◽  
High Sensitivity ◽  
Physical And Chemical Properties ◽  
Sensor Performance ◽  
Semiconducting Material ◽  
Physical And Chemical ◽  
And Chemical Properties

The performance of nanocomposites semiconducting material used as a sensor is very much depending upon physical and chemical properties of the material. In this paper we address sensitivity of ZnSnO3thin film deposited by hydrothermal deposition in terms of its behavior towards humidity variations. The electrical, optical and structural properties of ZnSnO3thin film deposit at different volume of solvent (50 ml and 70 ml) grown by novel deposition of ZnSnO3hydrothermal with low temperature 95°C are also reviewed. The sensor performance of ZnSnO3thin film prepared at 50 ml volume show high sensitivity towards humidity. Using FESEM it was noted that the nanocube of ZnSnO3thin films growth on ZnO template with the size of nanocube is 100 to 140nm by varying the volume of the solvent.

scholarly journals Raman and Fluorescence Spectroscopy of CeO2, Er2O3, Nd2O3, Tm2O3, Yb2O3, La2O3, and Tb4O7

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Jianlan Cui ◽  
Gregory A. Hope
Keyword(s):  
Rare Earth ◽  
Energy Levels ◽  
Fluorescence Emission ◽  
Chemical Properties ◽  
Rare Earth Oxide ◽  
Raman Shift ◽  
Laser Sources ◽  
Induced Changes ◽  
Physical And Chemical ◽  
Good Agreement

To better understand and ascertain the mechanisms of flotation reagent interaction with rare earth (RE) minerals, it is necessary to determine the physical and chemical properties of the constituent components. Seven rare earth oxides (CeO2, Er2O3, Nd2O3, Tm2O3, Yb2O3, La2O3, and Tb4O7) that cover the rare earth elements (REEs) from light to heavy REEs have been investigated using Raman spectroscopy. Multiple laser sources (wavelengths of 325 nm, 442 nm, 514 nm, and 632.8 nm) for the Raman shift ranges from 100 cm−1to 5000 cm−1of these excitations were used for each individual rare earth oxide. Raman shifts and fluorescence emission have been identified. Theoretical energy levels for Er, Nd, and Yb were used for the interpretation of fluorescence emission. The experimental results showed good agreement with the theoretical calculation for Er2O3and Nd2O3. Additional fluorescence emission was observed with Yb2O3that did not fit the reported energy level diagram. Tb4O7was observed undergoing laser induced changes during examination.

scholarly journals Determination of physiochemical properties of Gum Arabic as a suitable binder in emulsion house paint

2016 ◽  
Vol 5 (1) ◽  
pp. 67-78
Author(s):  
Ali L. Yaumi ◽  
Ahmed M. Murtala ◽  
Habiba D. Muhd ◽  
Fatima M. Saleh
Keyword(s):  
Chemical Properties ◽  
Gum Arabic ◽  
Acacia Senegal ◽  
Physiochemical Properties ◽  
Binding Strength ◽  
Wide Range ◽  
Percentage Concentration ◽  
Physical And Chemical ◽  
Good Agreement

Gum Arabic “GA” is an organic adhesive produced from a tree called named Acacia Senegal. The gum has a wide range of industrial uses, especially in areas of feeds, textiles, and pharmaceuticals. It is used as emulsifier and serves mostly as stabilizer in both cosmetic and food products which contains oil water interface. GA sample was collected, formulated and prepared into various concentrations ranging from 20%w/v to 85%w/v. The quality and applicability of well characterized materials are directly related to their physical and chemical properties. From the physiochemical analysis, the result revealed that all the samples were slightly acidic (pH ranging from 4.81-6.41). This range is in good agreement with reported pH values for gum arabic and other Acacia gums by several authors. . The binding strength increases as the number of days increases for example in sample F (50%w/v) gum Arabic concentration increases from 1.5 in the 1st day to 1.97 in the 28th day. The samples prepared are denser than water which indicates that the density increases as the percentage concentration of the samples increases and the relative density of the gum solution is independent on time. The binding strength of sample G (75%w/v) gum concentration compared well to that of polyvinyl acetate (PVA). International Journal of Environment Vol. 5 (1) 2016,  pp: 67-78

scholarly journals Mechanistic modeling of pesticide uptake with a 3D plant architecture model

2021 ◽  
Author(s):  
Helena Jorda ◽  
Katrin Huber ◽  
Asta Kunkel ◽  
Jan Vanderborght ◽  
Mathieu Javaux ◽  
...  
Keyword(s):  
Root Zone ◽  
Chemical Properties ◽  
Mechanistic Modeling ◽  
The European Union ◽  
Architecture Model ◽  
Single Root ◽  
Solute Uptake ◽  
Physical And Chemical ◽  
And Diffusion ◽  
Good Agreement

Abstract A new root solute uptake model based on a lumped version of the Trapp model (Trapp, 2000) was implemented in a coupled version of R-SWMS-ParTrace models for 3-D water flow and solute transport in soil and roots. Solute uptake was modeled as two individual processes: advection with the transpiration stream and diffusion through the root membrane. We parameterized the model for a FOCUS scenario used in the European Union for pesticide registration. Simulation with a single root showed a good agreement with the results produced by the 1D PEARL model. Simulations with a complex root system predicted larger water uptake from the upper root zone, leading to larger pesticide uptake when pesticides are concentrated in the upper root zone. Dilution of root water concentrations at the top root zone with water with low pesticide concentration taken up from the bottom of the root zone lead to larger uptake of solute when uptake was simulated as a diffusive process. This illustrates the importance of modeling uptake mechanistically and considering root and solute physical and chemical properties, especially when root-zone pesticide concentrations are non uniform.

Statistical criteria of stellar population types

1966 ◽  
Vol 24 ◽  
pp. 101-110
Author(s):  
W. Iwanowska
Keyword(s):  
Stellar Population ◽  
Chemical Properties ◽  
Spectrophotometric Study ◽  
Physical And Chemical Properties ◽  
Population Type ◽  
The Galaxy ◽  
Distribution Parameters ◽  
Physical And Chemical ◽  
Statistical Criteria ◽  
And Chemical Properties

In connection with the spectrophotometric study of population-type characteristics of various kinds of stars, a statistical analysis of kinematical and distribution parameters of the same stars is performed at the Toruń Observatory. This has a twofold purpose: first, to provide a practical guide in selecting stars for observing programmes, second, to contribute to the understanding of relations existing between the physical and chemical properties of stars and their kinematics and distribution in the Galaxy.

Biophysical Measurement of Molecular Weight of Foot-and-Mouth Disease RNA Fragments

1974 ◽  
Vol 32 ◽  
pp. 262-263
Author(s):  
Sydney S. Breese ◽  
Howard L. Bachrach
Keyword(s):  
Chemical Properties ◽  
Foot And Mouth Disease ◽  
Mouth Disease ◽  
Distilled Water ◽  
Bovine Plasma ◽  
Mouth Disease Virus ◽  
Foot And Mouth ◽  
Carbon Coated ◽  
Rna Fragments ◽  
Physical And Chemical

Continuing studies on the physical and chemical properties of foot-and-mouth disease virus (FMDV) have included electron microscopy of RNA strands released when highly purified virus (1) was dialyzed against demlneralized distilled water. The RNA strands were dried on formvar-carbon coated electron microscope screens pretreated with 0.1% bovine plasma albumin in distilled water. At this low salt concentration the RNA strands were extended and were stained with 1% phosphotungstic acid. Random dispersions of strands were recorded on electron micrographs, enlarged to 30,000 or 40,000 X and the lengths measured with a map-measuring wheel. Figure 1 is a typical micrograph and Fig. 2 shows the distributions of strand lengths for the three major types of FMDV (A119 of 6/9/72; C3-Rezende of 1/5/73; and O1-Brugge of 8/24/73.

Tailoring microstructures of materials through biomimetics

1993 ◽  
Vol 51 ◽  
pp. 500-501
Author(s):  
Mehmet Sarikaya ◽  
Ilhan A. Aksay
Keyword(s):  
Chemical Properties ◽  
Design And Synthesis ◽  
Structure Sensitive ◽  
Macro Scale ◽  
Methods Of Synthesis ◽  
Successive Level ◽  
Engineering Materials ◽  
Physical And Chemical ◽  
And Chemical Properties ◽  
Synthesis Of Materials

Biomimetics involves investigation of structure, function, and methods of synthesis of biological composite materials. The goal is to apply this information to the design and synthesis of materials for engineering applications.Properties of engineering materials are structure sensitive through the whole spectrum of dimensions from nanometer to macro scale. The goal in designing and processing of technological materials, therefore, is to control microstructural evolution at each of these dimensions so as to achieve predictable physical and chemical properties. Control at each successive level of dimension, however, is a major challenge as is the retention of integrity between successive levels. Engineering materials are rarely fabricated to achieve more than a few of the desired properties and the synthesis techniques usually involve high temperature or low pressure conditions that are energy inefficient and environmentally damaging.In contrast to human-made materials, organisms synthesize composites whose intricate structures are more controlled at each scale and hierarchical order.

Response of corn (Zea mays L.) to various organic-based fertilizers in marginal upland of Sta. Rita, Samar

2017 ◽  
pp. 31-43
Author(s):  
Berta Ratilla ◽  
Loreme Cagande ◽  
Othello Capuno
Keyword(s):  
Block Design ◽  
Management Strategies ◽  
Chemical Properties ◽  
Organic Fertilizers ◽  
Growth And Yield ◽  
Physical And Chemical Properties ◽  
Total N ◽  
Randomized Complete Block Design ◽  
Physical And Chemical ◽  
And Chemical Properties

Organic farming is one of the management strategies that improve productivity of marginal uplands. The study aimed to: (1) evaluate effects of various organic-based fertilizers on the growth and yield of corn; (2) determine the appropriate combination for optimum yield; and (3) assess changes on the soil physical and chemical properties. Experiment was laid out in Randomized Complete Block Design, with 3 replications and 7 treatments, namely; T0=(0-0-0); T1=1t ha-1 Evans + 45-30-30kg N, P2O5, K2O ha-1; T2=t ha-1 Wellgrow + 45-30-30kg N, P2O5, K2O ha-1; T3=15t ha-1 chicken dung; T4=10t ha-1 chicken dung + 45-30-30kg N, P2O5, K2O ha-1; T5=15t ha-1 Vermicast; and T6=10t ha-1 Vermicast + 45-30-30kg N, P2O5, K2O ha-1. Application of organic-based fertilizers with or without inorganic fertilizers promoted growth of corn than the control. But due to high infestation of corn silk beetle(Monolepta bifasciata Horns), its grain yield was greatly affected. In the second cropping, except for Evans, any of these fertilizers applied alone or combined with 45-30-30kg N, P2O5, K2O ha-1 appeared appropriate in increasing corn earyield. Soil physical and chemical properties changed with addition of organic fertilizers. While bulk density decreased irrespective of treatments, pH, total N, available P and exchangeable K generally increased more with chicken dung application.

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