Showing papers in "Instrumentation Science & Technology in 2002"
TL;DR: A global strategy aimed at extending the breadth and throughput of proteomic measurements based on utilizing polypeptide “accurate mass tags” produced by global protein enzymatic digestion provides greater confidence in the assignment of protein identifications than possible with conventional tandem mass spectrometric data alone.
Abstract: We review a global strategy aimed at extending the breadth and throughput of proteomic measurements based on utilizing polypeptide “accurate mass tags” produced by global protein enzymatic digestion. The two-stage strategy described employs conventional mass spectrometric techniques to provide initial putative identifications of peptides based on searching genome databases using the partial sequence information gleaned from tandem mass spectrometric data. The second stage of the strategy utilizes advanced mass spectrometric instrumentation to “validate” those putative identifications initially made using conventional tandem mass spectrometric data. Specifically, the high mass accuracy provided by more advanced instrumentation is utilized and ultimately correlated with the conventional tandem mass spectrometric data (along with each of the peptides' liquid chromatographic elution time) to validate the putative identifications. The strategy described provides greater confidence in the assignment of...
112 citations
TL;DR: In this article, an RBC-II type rotating-bomb calorimeter with digital indicator, wherein an integrated circuit is employed, aiming at promoting the precision and accuracy of the experimental thermochemistry, is developed.
Abstract: Based on an RBC-I type rotating-bomb calorimeter, an RBC-II type rotating-bomb calorimeter with digital indicator, wherein an integrated circuit is employed, aiming at promoting the precision and accuracy of the experimental thermochemistry, is developed. The accuracy uncertainty of the present calorimeter has been reduced from 1.6 × 10−3 to 4.68 × 10−4 by calibration with the standard benzoic acid. The constant volume combustion enthalpies of the new complexes of Cr(His)(NO3)3 3H2O (A), Cr(His)2(NO3)3 3H2O (B), and Cr(His)3(NO3)3 3H2O (C) have been determined by the RBC-II type rotating-bomb calorimeter. The standard formation enthalpies of the complexes have been calculated; they are −1160.22±2.64 kJ mol−1, −1844.91±4.33 kJ mol−1, and −5400±5.08 kJ mol−1, respectively.
75 citations
TL;DR: The ERETIC method provides an electronic reference signal which can be used to determine concentrations by NMR spectroscopy as mentioned in this paper, but the long-term stability is dramatically improved.
Abstract: The ERETIC method provides an electronic reference signal which can be used to determine concentrations by NMR spectroscopy. We have evaluated two improvements of the method: addition of a broadband antenna in the NMR probe and digital generation of the ERETIC signal. Five solutions of dioxane, 9.12 mM, and sodium lactate in D2O, at concentrations ranging from 4.24 mM to 43.95 mM, were used to evaluate these modifications to the method. The broadband antenna does not affect the efficiency of the method, but increases its flexibility. The digital synthesis does not modify the precision, the accuracy, or the short-term stability. However, the long-term stability is dramatically improved. The advantage of this development is that the ERETIC method can be implemented on most modern NMR spectrometers without needing any hardware modification.
34 citations
TL;DR: In this paper, hydrogen gas and acetone vapor were found to emanate from human skin, and a modified Tedlar bag or aluminum bag was used to cover a finger or the whole palm.
Abstract: We have found that hydrogen gas and acetone vapor emanate from human skin. Emanation gases from human skin were collected for 5–10 min from arm, palm, or forefinger with a homemade probe and bags. The trapped gases were analyzed by gas chromatography, and hydrogen gas and acetone vapor were found to exist in all subjects. The probe (44 mm outer diameter, 6 mm height and inner volume of 3.8 mL) directly covered a 9.4 cm2—flat skin surface of the arm, and a modified Tedlar bag or aluminum bag could cover a finger or the whole palm. The average rates of acetone vapor and hydrogen gas released from human skin (15 subjects) is 80–800 and 5–50 pg cm−2 min−1, respectively. There is a good linear relationship between the emanation rate and the concentration of those gases in human breath. Correlation factors for acetone vapor and hydrogen gas are 0.81 and 0.66, respectively. The proposed non-invasive clinical technique imposes only very minor physical stress on a subject during sampling.
32 citations
TL;DR: In this article, a back photopyroelectric (PPE) configuration with opaque sample and thermally thick sample and sensor was applied in order to obtain room temperature values of the thermal diffusivity of some (semi) liquid materials.
Abstract: The back photopyroelectric (PPE) configuration, with opaque sample and thermally thick sample and sensor, was applied in order to obtain room temperature values of the thermal diffusivity of some (semi)liquid materials. The methodology is based on a sample's thickness scan, and not on a frequency scan as usually happens. The possibility of controlling, very accurately, the sample's thickness variation, leads to very accurate and reproducible values for the thermal diffusivity. A special detection cell was designed in order to control the sample's thickness within 1 μm precision. Due to the high accuracy of the results one can study, via the thermal diffusivity, processes as sedimentation, the capture of water molecules by OH radicals in alcohol–water mixtures, or the quality of lipids (i.e., margarines).
27 citations
TL;DR: In this paper, the same authors applied photopyroelectric calorimetry in the front (inverse) configuration with thermally thick sensor and sample, and optically opaque sensor to measure the thermal effusivity of some fats and water-based juice products.
Abstract: Photopyroelectric calorimetry, in the front (inverse) configuration (with thermally thick sensor and sample, and optically opaque sensor), was applied to measure the thermal effusivity of some fats and water-based juice products. The information was obtained via a frequency scan of the phase of the pyroelectric signal; the measurements need no calibration. The main advantages of this configuration above the other two previously proposed front schemes are: (i) it does not require the use of very thin foils or expensive semitransparent sensors; (ii) the information is contained in the phase of the signal (and not in the amplitude as usual), which is independent of the power fluctuations of the radiation source and, consequently, the results are more accurate and reproducible.
24 citations
TL;DR: In this article, the experimental diffusion coefficients of CO and CO2 into various percentage mixtures of H2 and He were compared with those calculated theoretically, using an empirical equation in which the percentage v/v composition of the gas mixtures and the theoretical values of the diffusion coefficients were taken care of as they were found from the Fuller-Schettler-Giddings equation.
Abstract: The new technique of reversed-flow gas chromatography has been used for the measurement of diffusion coefficients of pure gases into gas mixtures. As pure gases, carbon monoxide (CO) and carbon dioxide (CO2), were used, while the gas mixtures consisted of hydrogen (H2) and helium (He) with various percentage compositions. The experimental diffusion coefficients of CO and CO2 into various percentage mixtures of H2 and He (25% v/v H2 + 75% v/v He, 50% v/v H2 + 50% v/v He, 75% v/v H2 + 25% v/v He) were compared with those calculated theoretically, using an empirical equation in which the percentage v/v composition of the gas mixtures and the theoretical values of the diffusion coefficients of the CO and CO2 into the pure gases of the mixture were taken care of as they were found from the Fuller–Schettler–Giddings equation. All the comparisons show small deviations, indicating that both the experimental technique of reversed-flow gas chromatography, and the proposed empirical equation, can be successfully use...
19 citations
TL;DR: In this article, a calorimetric unit was designed, manufactured, assembled, and tested, and the stability and sensibility parameters of each of the four thermopiles were determined, and were determined to be 80μV and 0.010μV−1, respectively.
Abstract: A calorimetric unit was designed, manufactured, assembled, and tested. It consists of a stainless steel cylindrical reaction cell, a thermal sensing system made of 4 thermopiles connected in series, and a spring actuated mechanical device for controlling the reactant's mixing process. The calorimeter measures the energy liberated in the reaction cell by measuring the heat conductive energy flux across the thermal sensing system. The stability and sensibility parameters of each of the 4 thermopiles were determined, and were determined to be 80 μV and 0.010 VM−1, respectively. Similarly, the sensibility of the calorimetric unit was determined for various levels of heat power generation. The sensibility of the calorimetric is 0.020 VW−1 in the 120 to 350 mW range. Results show that the stability and sensibility parameters of the calorimeter are unaffected by the heat energy power generated in the reaction cell of the calorimeter.
19 citations
TL;DR: In this paper, a new application of an inverse gas chromatographic technique, known as Reversed Flow Gas Chromatography (RFGC), which permits the experimental measurement of local isotherms, θ(p, T, ϵ) is presented.
Abstract: A new application of an inverse gas chromatographic technique, known as Reversed Flow Gas Chromatography (RFGC), which permits the experimental measurement of local isotherms, θ( p, T, ϵ) is presented. The method does not use analytical or numerical solutions of the classical integral equation comprising the energy distribution function, f(ϵ), as unknown, but it is based on a time function of gas chromatographic (GC) peaks obtained by short flow reversals of the carrier gas. It can be used for the measurement of local adsorption isotherms θ, as well as for the estimation of the related parameters such as local energies of adsorption ϵ, local adsorbed concentrations c s *, and local maximum monolayer capacities c max *. As a model system, we selected oxygen's adsorption onto three-way silica supported 25% Pt+75% Rh alloy catalyst.
15 citations
TL;DR: In this paper, the authors describe the implementation of inline methods for gas chromatographic (GC) analysis of tracers in both the laboratory and in the field, which can reduce costs associated with sampling, transport, storage, and laboratory analyses.
Abstract: Partitioning tracer techniques have been demonstrated to be effective for characterizing the amount of nonaqueous phase liquid (NAPL) contaminants present in aquifers. Partitioning interwell tracer tests (PITTs) typically involve the collection of a large number of groundwater samples for subsequent laboratory analysis. This paper describes the implementation of inline methods for gas chromatographic (GC) analysis of tracers in both the laboratory and in the field. Benefits of inline analysis include reduced costs associated with sampling, transport, storage, and laboratory analyses, minimization of tracer mass loss during sample collection and transport, and immediate access to data for on-site decision making. A series of laboratory PITT experiments were conducted in a two-dimensional flow chamber packed with various combinations of clean sand and NAPL, resulting in a range of average residual saturation, S N , values. Inline chromatographic analysis enabled automation of these experiments whil...
13 citations
TL;DR: A femtoliter microwell array system has been developed for ultrasensitive DNA/mRNA detection using molecular beacon (MB) DNA probes that will be highly useful for single cell gene profiling and for multiple gene determination in disease diagnosis.
Abstract: DNA/mRNA analysis and genetic mutation detection are important in biomedical sciences, clinical diagnosis, and environmental monitoring. In this study, a femtoliter microwell array system has been developed for ultrasensitive DNA/mRNA detection using molecular beacon (MB) DNA probes. The microwell array system, with laser-induced fluorescence imaging, can be used to achieve a detection limit of 9 Rhodamin 6G molecules in 28 fL (28 × 10−15 L) wells in this array. Hybridization kinetics of the MBs and their complementary DNA targets has been monitored with a concentration detection limit of 3.0 nM. As few as 50 target DNA copies can be monitored in each well. The specificity of MB and the effect of DNA target concentration on the MB hybridization kinetics have been investigated in femtoliter wells. Analysis of specific rat γ-actin mRNA sequence amplified by polymerase chain reaction (PCR) and simultaneous measurement of multiple analytes have also been studied with this microwell array system. As t...
TL;DR: In this article, a new method for fast diagnosis and mapping of tooth caries is suggested, based on autofluorescence and application of Fourier transform imaging microscopy, which provides simultaneous fluorescence spectra at all pixels of the examined sample.
Abstract: A new method for fast diagnosis and mapping of tooth caries is suggested. The method is based on autofluorescence and application of Fourier transform imaging microscopy. This device provides simultaneous fluorescence spectra at all pixels of the examined sample. A cooled CCD detector, directly connected to the spectrometer, collects the imaging interferograms and allows for spectral mapping. The feasibility of this method was evaluated by examining human teeth for caries detection. Images and the corresponding spectra were acquired at various tooth regions. It was found that a distinct spectral feature characterizes the carious regions. Spectral analysis allows for detection of even early stages of caries, while the associated mapping capability allows for morphological characterization. The spatial resolution depends on the specific optical setup used, and in our case it was ca. 1 μm. These findings suggest that this technique may be further developed and applied for clinical detection of initi...
TL;DR: The system is equipped with a fully rotary valve which serves in preparation of the set of standard solutions from a single stock solution, and is expected to be useful for routine analysis.
Abstract: The flow system has been designed for the purpose of performing analytical determinations according to the integrated calibration method. The system is equipped with a fully rotary valve which serves in preparation of the set of standard solutions from a single stock solution. A standard is exposed to measurements in two forms: by itself, and as a mixture with a sample. Each of the two solutions is able to be propelled to the detector at two different flow rates. As a consequence, the measurement information gathered during a single calibration run permits calculation of several estimations of an analytical result, in both the interpolative and extrapolative manner. Since some estimations are independent of each other, the final result is reliable in terms of accuracy, more than if using a conventional calibration approach. Owing to the instrumental simplicity and analytical efficiency, the system is expected to be useful for routine analysis.
TL;DR: In this article, an automated system for the on-line monitoring of R-captopril, based on the concept of sequential injection analysis with an amperometric biosensor (based on D-amino acid oxidase) as detector, is described.
Abstract: An automated system for the on-line monitoring of R-captopril, based on the concept of sequential injection analysis with an amperometric biosensor (based on D-amino acid oxidase) as detector, is described. The sampling rate is 80 samples per hour with an RSD <0.22% in the linear range between 0.2 and 1.0 μmol/L. The detection limit is 160 nmol/L.
TL;DR: In this article, the decomposition reaction of hydrochlorothiazide was studied using a simultaneous TG-DTA unit, in an inert atmosphere of flowing nitrogen, and the compound was subjected to a temperature ramp of 10°C/min from ambient to 600°C.
Abstract: Hydrochlorothiazide has been studied alone and in combination with excepients which make up a commercial product. This study focuses on the decomposition of hydrochlorothiazide alone. The decomposition reaction of hydrochlorothiazide was studied using a simultaneous TG-DTA unit, in a an inert atmosphere of flowing nitrogen. The compound was subjected to a temperature ramp of 10°C/min from ambient to 600°C. Mass spectrometry was used as a adjunctary technique to identify the products of the decomposition reaction. It was observed that hydrochlorothiazide decomposed via a multistage reaction following melting, with the rate controlling step being a diffusion controlled reaction. The electron spray ionization mass spectrum of the fragmented hydrochlorothiazide shows an abundance of sulphur dioxide, suggesting that this chemical is a major part of the decomposition volatiles lost in the thermal reaction.
TL;DR: In this article, a continuous imprinted polymer rod was prepared, in situ, by using L-phenylalanine derivatives as template molecules, methacrylic acid (MAA) as functional monomer, ethylene dimethacrylate as cross linking agent.
Abstract: A continuous imprinted polymer rod was prepared, in situ, by using L-phenylalanine derivatives as template molecules, methacrylic acid (MAA) as functional monomer, ethylene dimethacrylate as cross linking agent. The enantiomer of DL-phenylalanine was successfully separated using a new TSM sensor as the detector. The separation system exhibited good sensitivity, selectivity, and ideal separation. When the sample amount was 10 μg, the selectivity factor, α, was 1.87 and the resolution, R s , was 1.09.
TL;DR: In this paper, the degradation products for folic acid under thermal stress were identified using various analytical techniques, such as infrared spectroscopy, mass spectrograms, and X-ray diffraction.
Abstract: The purpose of this study was to identify the degradation products for folic acid which may form under thermal stress. An attempt was made to identify each of the decomposition products using various analytical techniques, such as infrared spectroscopy, mass spectroscopy, and X-ray diffraction, which suggested that the glutamic acid fragment of folic acid is lost first, as evidenced by acid loss and amide enhancement in the IR spectra. The vitamin was ultimately degrading to carbon fragments and further identification was not necessary.
TL;DR: In this article, laser-induced fluorescence (LIF) techniques, based on streak camera detection, were used to determine the level of hydrocarbons in the groundwater aquifers of Kuwait.
Abstract: Laser-induced fluorescence (LIF) techniques, based on streak camera detection, were used to determine the level of hydrocarbons in the groundwater aquifers of Kuwait. An appropriate classification algorithm, involving discriminant analysis, was used as a rapid in situ screening tool. Forty-two wells distributed throughout the country were sampled and included in the study. These were subjected to analysis by the standard USEPA 418.1 infrared method as well as the LIF method. The infrared analysis focused on the measurement of total petroleum hydrocarbons (TPH). Samples from wells showing high levels of hydrocarbons were also subjected to gas chromatography/mass spectrometry (GCMS) analysis for polycyclic aromatic hydrocarbons (PAHs).
TL;DR: In this article, a long-path ozone integrated measurements with a CO2-laser DIAL system were performed in Madrid City during a “vehicle-free” day.
Abstract: Long-path ozone integrated measurements with a CO2-laser DIAL system were performed in Madrid City during a “vehicle-free” day. The results showed a strong correlation between human activity and ozone photochemical generation. The ozone concentration follows, even quantitatively, the same trend of the overall traffic intensity as long as both UV-B radiation and NO2 are present. An average decrease of 12.3±1.2% of the intensity of vehicle traffic during the “free-vehicle” day resulted in a lowering the ozone burden by almost 14.4±1.4%. This new type of information can stimulate the development of local models to understand the dynamic underlying urban pollution. The results, indeed, show the effectiveness of such a measure to reduce the ozone burden on human and plant health.
TL;DR: The high sensitivity that can be attained by enzymatic amplification via substrate cycling and mediated by the redox polymer, has been verified by on-line interfacing of a rotating bioreactor and continuous- flow/stopped-flow/continuous-flow processing system.
Abstract: The high sensitivity that can be attained by enzymatic amplification via substrate cycling and mediated by the redox polymer [Os(bpy)2ClPyCH2NHpoly(allylamine) (Os-PAA), has been verified by on-line interfacing of a rotating bioreactor and continuous-flow/stopped-flow/continuous-flow processing system. The determination of glucose was possible with a limit of detection of 20 fmol L−1 in the processing of as many as 30 samples per hour. Determination at such low levels is of interest in several situations encountered in fermentation biotechnology and clinical chemistry, and for the determination in culture broths; it illustrates the capabilities of the proposed approach. Glucose oxidase and Os-PAA were covalently immobilized on a glassy carbon electrode surface (upper cell body), Glucose dehydrogenase [EC 1.1.1.47] was immobilized on a disk that can be rotated. Substrate cycling was realized via NADH/NAD+ that, in conjunction with glucose dehydrogenase, regenerates glucose, the substrate in the gl...
TL;DR: In this article, the influence of different thermal insulation fillings on dynamic properties of industrial resistance temperature probes, based on a thin-film platinum resistance temperature detector, was investigated in water simulations.
Abstract: This paper presents some results of experimental research addressing the influence of different thermal insulation fillings on dynamic properties of industrial resistance temperature probes, based on a thin-film platinum resistance temperature detector. The experiments were carried out with four jacket thin-film resistance temperature probes, all having identical protection tube geometry, yet differing in the thermal insulation filling materials. Further, a comparison between transient response characteristics in water established experimentally and those based on simulations with electric–thermal analogy, is given. The results of these analyses can be applied to enhance the dynamic response of temperature measurement made by temperature probes in water.
TL;DR: In this paper, a disposable glass sensor head has been constructed for a fiber optic spectrofluorimeter consisting of a Xe lamp light source, a bifurcated optical fiber, a PMT detector with a monochromator, and a PC for data analysis.
Abstract: A disposable glass sensor head has been constructed for a fiber optic spectrofluorimeter. The fiber optic spectrofluorometer consists of a Xe lamp light source, a bifurcated optical fiber, a PMT detector with a monochromator, and a PC for data analysis. The developed novel glass sensor head avoids contact between the optical fiber and the analyte sample. It does not show any background interference above 340 nm; therefore, analyte can be easily monitored above 350 nm. Thus, the sensor is simple, flexible, inexpensive, and is capable of operation in hostile environments. The sensor head has been tested for monitoring polycyclic aromatic hydrocarbons, principally perylene and anthracene, at environmental levels (ppb) and for sensing fluorescent probe (chemical transducer) in polymer films.
TL;DR: In this article, the development of an automated computer-aided sequential injection analysis (SIA) system and its application to laboratory automation is described. But the software, based on graphic programming language LabVIEW, is described in detail.
Abstract: The paper presented deals with the development of an automated computer-aided sequential injection analysis (SIA) system and its application to laboratory automation. In Part I, hardware and technical parameters of the SIA system were described. Part II introduces original lab-developed operational software (FaFSIA), enabling one to control the cited SIA system and to process experimental data, including their presentation. The software, based on graphic programming language LabVIEW, is described in detail.
TL;DR: In this article, an energy dispersive x-ray fluorescence analysis is applied for determining the spatial distribution of elemental concentrations of emboli in the vascular system, where fluorescent Kα x-rays of elements were detected so that the elemental concentration could be determined for these elements.
Abstract: An energy dispersive x-ray fluorescence analysis is applied for determining the spatial distribution of elemental concentrations of emboli in the vascular system. The fluorescent Kα x-rays of elements were detected so that the elemental concentration could be determined for these elements. For this measurement, Am-241 and Fe-55 radioisotopes were used for excitation of samples and a Si(Li) detector together with an ND66B multichannel analyzer was used for counting of Kα x-rays.
TL;DR: A flavoenzyme, glucose-3-dehydrogenase (G3DH) from Halomonas sp.
Abstract: A flavoenzyme, glucose-3-dehydrogenase (G3DH) from Halomonas sp. α-15 strain, possessed broad substrate specificity and site-specific reaction against various sugars. We constructed an amperometric enzyme electrode employing G3DH and also developed a multi-sugar analysis system combined with the G3DH sensor and sugar analysis chromatography. This system can discriminate the 4 components of sugar, i.e., glucose, 1,5-anhydro-D-glucitol, trehalose, and N-carbamoyl-β-D-glucopyranosylamine mixture and it can determine each concentration from 2 mM to 10 mM.
TL;DR: In this article, a fused-silica capillary that is wall-modified via chemically bonding histidine functional groups to the capillary wall, is described, and changes in the type, concentration, and pH of the buffer, as well as the applied voltage, are performed to determine the optimum condition for the simultaneous separation of neutral and anionic plant phenols.
Abstract: A fused-silica capillary that is wall-modified, via chemically bonding histidine functional groups to the capillary wall, is described. With benzyl alcohol as neutral marker, the electroosmotic flow (EOF) of the bonded phase is reversed and the migration velocity increases slightly as the pH decreases. Changes in the type, concentration, and pH of the buffer, as well as the applied voltage, were performed to determine the optimum condition for the simultaneous separation of neutral and anionic plant phenols. A separation of (+)-catechin, gallic acid, caffeic acid, (−)-epicatechin, salicylic acid, quercetin, and p-coumaric acid could be obtained on a 100 cm × 75 μm I.D. column under acetate buffer (10 mM, pH 5.0) and an applied voltage of −20 kV with good peak shapes and efficiencies over the range 7.46 × 105 to 3.86 × 106 plates per meter. The amount of plant phenols in wines has also been determined with the established method. Quantitative analysis was performed by the standard addition method. The mech...
TL;DR: In this article, an on-line magnetic flow chamber was constructed using 1.0 I.D. × 1.58 O.mm Teflon tubing that was attached to an electromagnet.
Abstract: Immunomagnetic separation (IMS) uses magnetic beads to facilitate separation of antibody-bound labeled antigens from free antigens in solution. Off-line immunomagnetic separation is time consuming due to the requirement of washing the magnetizable beads between assays and the multiple steps involved in the separation process. On-line IMS, in the flow injection mode, can overcome the disadvantages of off-line IMS, such as multiple washing steps. The purpose of this work is to develop, optimize, and validate an on-line magnetic separation flow chamber in the flow injection mode, suitable for post-column immunoreaction detection. The ends of the flow chamber were connected to the flow injection system. The on-line magnetic flow chamber was constructed using 1.0 I.D. × 1.58 O.D.mm Teflon tubing that was attached to an electromagnet. The electromagnet was constructed by wrapping a 305 × 25 × 40 mm block of hard steel with fine copper wire which was supplied with direct current (dc). The magnetic field...
TL;DR: The ever increasing demand for analyses in clinical, agricultural, pharmaceutical, industrial, and process analytical control has led to the development of Sequential Injection Analysis (SIA), which requires synchronisation of sample zone injection with the start of each flow cycle.
Abstract: The ever increasing demand for analyses in clinical, agricultural, pharmaceutical, industrial, and process analytical control has led to the development of Sequential Injection Analysis (SIA) [1]. ...
TL;DR: In this article, the potential of photoacoustic spectroscopy for monitoring the effect of environmental stress on leaves was investigated, and the effects of the accuracy, heterogeneous nature within a selected leaf class, characteristics insolation and the soil type at a site of measurement were also considered.
Abstract: Potential of photoacoustic (PA) spectroscopy for monitoring the effect of environmental stress on leaves was investigated. Dandelion (Taraxacum officinale), a widely distributed perennial weed, having large leaves and being sensitive to environmental contamination, was selected as the most suitable model plant. PA study conducted on dandelion leaves exposed to different environmental stresses and treated with methylviologen (MV) shows a decrease of photosynthetic energy storage (ES) with increasing concentration of environmental pollutant. Depending on the place of collection, ES values in these plants ranged from 43 to 65. The effects of the accuracy, heterogeneous nature within a selected leaf class, characteristics insolation and the soil type at a site of measurement were also considered.
TL;DR: In this article, a new viscosity-capillary dipometer was designed and used in an investigation of the viscosities for calcium hydrogen phosphate and calcium oxalate suspensions, and the data showed that this method is suitable for suspensions.
Abstract: A new viscosity–capillary dipometer was designed and used in this investigation. Comparing this piece of equipment with other viscometers, the capillary dipometer is accurate, easy to operate, and much less expensive. The viscosities for calcium hydrogen phosphate and calcium oxalate suspensions are determined using the capillary dipometer. The data shows that this method is suitable for suspensions. This method could also be applied to other liquid dosage forms (i.e., emulsions) to provide quick and accurate results.