Plant sampling: a review

1993 ◽  
Vol 33 (8) ◽  
pp. 1007 ◽  
Author(s):  
JB Robinson
Keyword(s):  
Plant Tissue ◽  
Tissue Sample ◽  
Mineral Nutrient ◽  
Tissue Analysis ◽  
Plant Analysis ◽  
Element Analysis ◽  
Sample Handling ◽  
Wide Range ◽  
Sampling Statistics ◽  
Multi Element Analysis

The steps involved in collecting and handling samples for plant analysis are described under the following headings: purpose for which the sample is collected; sampling statistics; sampling strategies; choice of tissue; sample handling; special sampling techniques. In any application of plant tissue analysis close attention should be given to the approaches which are used to develop the critical values or ranges that are used. In diagnostic and prognostic use of plant analysis the statistics of the sampling procedure should be well understood, so that a sample which properly represents the crop or planting can be collected. When diagnosis is the primary objective the sampling unit may be as small as a single plant. It is important that contamination of the sample with nutrient sprays or other materials is understood and recorded. Washing may not be possible, particularly when samples are collected by unskilled people at a site distant from the analytical laboratory. Although washing with detergents or weak acids can remove contamination, there will remain some doubt as to the efficiency of the washing procedure. Samples which are to be used for sap tests immediately after collection for nitrate-nitrogen should be handled more carefully than those destined after drying for multi-element analysis at a remote laboratory. Ideally the respiratory loss of dry weight from samples should be minimised when the samples are destined for conventional multi-element analysis. Where certain aspects of sample handling are critical to the success of the test they should be emphasised to potential users. A wide range of plant tissues other than the commonly collected leaves and petioles has been used for assessment of mineral nutrient status, including juice, fruit, and shoot tips. Each of these presents different problems in sample collection handling and storage. Tests based on enzyme activity and other biochemical or physiological indicators probably present the most difficult sample handling problems, but these tests are not widely used. A number of sampling issues which arise from the author's experience with commercial tissue analysis services are raised. These include such matters as the extent of training of the personnel who do the sampling, contamination and transport to the laboratory. Although more attention to these issues is needed in practice, plant tissue analysis continues to be a most valuable tool in the hands of the informed manager.

Measuring the Elastic Modulus of Small Tissue Samples

1998 ◽  
Vol 20 (1) ◽  
pp. 17-28 ◽  
Author(s):  
R.Q. Erkamp ◽  
P. Wiggins ◽  
A.R. Skovoroda ◽  
S.Y. Emelianov ◽  
M. O'Donnell
Keyword(s):  
Elastic Modulus ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Tissue Sample ◽  
Clinical Tool ◽  
Limited Sample ◽  
Element Analysis ◽  
Tissue Samples ◽  
Small Tissue ◽  
Wide Range

Independent measurements of the elastic modulus (Young's modulus) of tissue are a necessary step in turning elasticity imaging into a clinical tool. A system capable of measuring the elastic modulus of small tissue samples was developed. The system tolerates the constraints of biological tissue, such as limited sample size (≤1.5 cm3) and imperfections in sample geometry. A known deformation is applied to the tissue sample while simultaneously measuring the resulting force. These measurements are then converted to an elastic modulus, where the conversion uses prior calibration of the system with plastisol samples of known Young's modulus. Accurate measurements have been obtained from 10 to 80 kPa, covering a wide range of tissue modulus values. In addition, the performance of the system was further investigated using finite element analysis. Finally, preliminary elasticity measurements on canine kidney samples are presented and discussed.

SHORT COMMUNICATION: A comparison of plant tissue digestion methods for nitrogen and phosphorus analyses

1995 ◽  
Vol 75 (2) ◽  
pp. 243-245 ◽  
Author(s):  
Y. K. Soon ◽  
Y. P. Kalra
Keyword(s):  
Plant Tissue ◽  
Nitrogen And Phosphorus ◽  
Digestion Method ◽  
Element Analysis ◽  
Dry Ashing ◽  
Kjeldahl Digestion ◽  
Digestion Methods ◽  
Multi Element Analysis ◽  
Nitrogen Phosphorus ◽  
Tissue Digestion

Four variations of the Kjeldahl digestion were compared with a H2SO4–H2O2 digestion for N and P analysis, and a microwve digestion method and a dry ashing procedure for P analysis. One Kjeldahl variant using a Na2SO4–Se catalyst was found to be suitable for multi-element analysis while doubling the per diem output of digestions compared with the H2SO4–H2O2 method, provided that P was analyzed by the molybdivanadate (MV) procedure. Key words: Kjeldahl digestion, nitrogen, phosphorus, plant tissue

Geospatial Soil and Plant Tissue Analysis of Sericea Lespedeza (Lespedeza cuneata) Invasion around Lake Issaqueena, South Carolina

2016 ◽  
Vol 47 (5) ◽  
pp. 630-638 ◽  
Author(s):  
Elena Mikhailova ◽  
Donald Hagan ◽  
Julia Sharp ◽  
Tristan Allerton ◽  
Kylie Burdette ◽  
...  
Keyword(s):  
South Carolina ◽  
Plant Tissue ◽  
Tissue Analysis ◽  
Lespedeza Cuneata ◽  
Sericea Lespedeza

scholarly journals Design of 3D Additively Manufactured Hybrid Structures for Cranioplasty

Materials ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 181
Author(s):  
Roberto De Santis ◽  
Teresa Russo ◽  
Julietta V. Rau ◽  
Ida Papallo ◽  
Massimo Martorelli ◽  
...  
Keyword(s):  
Physical Models ◽  
Cranial Bone ◽  
Head Model ◽  
Rigid Sphere ◽  
Element Analysis ◽  
Aliphatic Polyesters ◽  
Hybrid Device ◽  
Wide Range ◽  
Hybrid Devices ◽  
Technical Solutions

A wide range of materials has been considered to repair cranial defects. In the field of cranioplasty, poly(methyl methacrylate) (PMMA)-based bone cements and modifications through the inclusion of copper doped tricalcium phosphate (Cu-TCP) particles have been already investigated. On the other hand, aliphatic polyesters such as poly(ε-caprolactone) (PCL) and polylactic acid (PLA) have been frequently investigated to make scaffolds for cranial bone regeneration. Accordingly, the aim of the current research was to design and fabricate customized hybrid devices for the repair of large cranial defects integrating the reverse engineering approach with additive manufacturing, The hybrid device consisted of a 3D additive manufactured polyester porous structures infiltrated with PMMA/Cu-TCP (97.5/2.5 w/w) bone cement. Temperature profiles were first evaluated for 3D hybrid devices (PCL/PMMA, PLA/PMMA, PCL/PMMA/Cu-TCP and PLA/PMMA/Cu-TCP). Peak temperatures recorded for hybrid PCL/PMMA and PCL/PMMA/Cu-TCP were significantly lower than those found for the PLA-based ones. Virtual and physical models of customized devices for large cranial defect were developed to assess the feasibility of the proposed technical solutions. A theoretical analysis was preliminarily performed on the entire head model trying to simulate severe impact conditions for people with the customized hybrid device (PCL/PMMA/Cu-TCP) (i.e., a rigid sphere impacting the implant region of the head). Results from finite element analysis (FEA) provided information on the different components of the model.

Improvement of the Detection Sensitivity of Edxrf Trace Element Analysis by Means of Efficient X-Ray Focusing Based on Strongly Curved Hopg Crystals

1995 ◽  
Vol 39 ◽  
pp. 109-117
Author(s):  
Burkhard Beckhoff ◽  
Birgit Kanngießer
Keyword(s):  
High Intensity ◽  
Focal Plane ◽  
Bragg Reflection ◽  
Pyrolytic Graphite ◽  
Trace Element Analysis ◽  
Detection Sensitivity ◽  
Element Analysis ◽  
X Ray ◽  
Wide Range ◽  
Very High

X-ray focusing based on Bragg reflection at curved crystals allows collection of a large solid angle of incident radiation, monochromatization of this radiation, and condensation of the beam reflected at the crystal into a small spatial cross-section in a pre-selected focal plane. Thus, for the Bragg reflected radiation, one can achieve higher intensities than for the radiation passing directly to the same small area in the focal plane. In that case one can profit considerably from X-ray focusing in an EDXRF arrangement. The 00 2 reflection at Highly Oriented Pyrolytic Graphite (HOPG) crystals offers a very high intensity of the Bragg reflected beam for a wide range of photon energies. Furthermore, curvature radii smaller than 10 mm can be achieved for HOPG crystals ensuring efficient X-ray focusing in EDXRF applications. For the trace analysis of very small amounts of specimen material deposited on small areas of thin-filter backings, HOPG based X-ray focusing may be used to achieve a very high intensity of monochromatic excitation radiation.

CFD Simulation of Fluid Flow Through Porous Media: Application to Decomposed Gases Flow Through Foam Pattern in Lost Foam Casting

Materials ◽  
2003 ◽  
Author(s):  
Sayavur I. Bakhtiyarov ◽  
Ruel A. Overfelt
Keyword(s):  
Cfd Simulation ◽  
Reynolds Numbers ◽  
Phase Flow ◽  
Flow Through Porous Media ◽  
Foam Material ◽  
Element Analysis ◽  
Wide Range ◽  
Flow Through ◽  
Foam Pattern ◽  
Lost Foam

Numerical simulation of decomposed gases through foam pattern was conducted using finite element analysis. A new kinetic model is proposed for gaseos phase flow between molten metal and foam material. The computations were performed for a wide range of Reynolds numbers. The results of the simulations are compared with the experiemental data obtained in this study.

NOVEL COUPLING CONSTRAINT TECHNIQUE FOR EXPLICIT FINITE ELEMENT ANALYSIS

2004 ◽  
Vol 01 (02) ◽  
pp. 309-328
Author(s):  
R. J. HO ◽  
S. A. MEGUID ◽  
R. G. SAUVÉ
Keyword(s):  
Finite Element ◽  
Current Method ◽  
Explicit Integration ◽  
Rotation Tensor ◽  
Element Analysis ◽  
Explicit Finite Element ◽  
Explicit Finite Element Analysis ◽  
Wide Range ◽  
Large Rotations ◽  
Generalized Constraint

This paper presents a unified novel technique for enforcing nonlinear beam-to-shell, beam-to-solid, and shell-to-solid constraints in explicit finite element formulations. The limitations of classical multi-point constraint approaches are examined at length, particularly in the context of explicit solution schemes. Novel formulation of a generalized constraint method that ensures proper element coupling is then presented, and its computer implementation in explicit integration algorithms is discussed. Crucial in this regard is the accurate and efficient representation of finite rotations, accomplished using an incremental rotation tensor. The results of some illustrative test cases show the accuracy and robustness of the newly developed algorithm for a wide range of deformation, including that in which large rotations are encountered. When compared to existing works, the salient features of the current method are in evidence.

Geographic determination of coffee beans using multi-element analysis and isotope ratios of boron and strontium

2014 ◽  
Vol 142 ◽  
pp. 439-445 ◽  
Author(s):  
Hou-Chun Liu ◽  
Chen-Feng You ◽  
Chiou-Yun Chen ◽  
Yu-Ching Liu ◽  
Ming-Tsung Chung
Keyword(s):  
Isotope Ratios ◽  
Element Analysis ◽  
Coffee Beans ◽  
Multi Element Analysis

Measurement and Calculation of Elastic Properties in Low Carbon Steel Sheet

2005 ◽  
Vol 495-497 ◽  
pp. 1591-1596 ◽  
Author(s):  
Vladimir Luzin ◽  
S. Banovic ◽  
Thomas Gnäupel-Herold ◽  
Henry Prask ◽  
R.E. Ricker
Keyword(s):  
Carbon Steel ◽  
Elastic Property ◽  
Elastic Properties ◽  
Steel Sheet ◽  
Low Carbon Steel ◽  
Low Carbon ◽  
Forming Process ◽  
Element Analysis ◽  
Wide Range ◽  
Carbon Steel Sheet

Low carbon steel (usually in sheet form) has found a wide range of applications in industry due to its high formability. The inner and outer panels of a car body are good examples of such an implementation. While low carbon steel has been used in this application for many decades, a reliable predictive capability of the forming process and “springback” has still not been achieved. NIST has been involved in addressing this and other formability problems for several years. In this paper, texture produced by the in-plane straining and its relationship to springback is reported. Low carbon steel sheet was examined in the as-received condition and after balanced biaxial straining to 25%. This was performed using the Marciniak in-plane stretching test. Both experimental measurements and numerical calculations have been utilized to evaluate anisotropy and evolution of the elastic properties during forming. We employ several techniques for elastic property measurements (dynamic mechanical analysis, static four point bending, mechanical resonance frequency measurements), and several calculation schemes (orientation distribution function averaging, finite element analysis) which are based on texture measurements (neutron diffraction, electron back scattering diffraction). The following objectives are pursued: a) To test a range of different experimental techniques for elastic property measurements in sheet metals; b) To validate numerical calculation methods of the elastic properties by experiments; c) To evaluate elastic property changes (and texture development) during biaxial straining. On the basis of the investigation, recommendations are made for the evaluation of elastic properties in textured sheet metal.

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