DISTANCE MEASUREMENTS USING FREQUENCY STABILIZED Nd:YAG LASERS

1996 ◽  
Vol 05 (03) ◽  
pp. 543-550
Author(s):  
VERED MAHAL ◽  
ADY ARIE
Keyword(s):  
Frequency Stability ◽  
Precise Determination ◽  
Phase Shifting ◽  
Distance Measurements ◽  
Fringe Contrast ◽  
Nd:Yag Lasers ◽  
Wide Range ◽  
Diode Pumped ◽  
Selection Of

Two diode-pumped tunable Nd:YAG lasers locked to sub-Doppler transitions of 127I2 and 133 Cs 2 are used as a source for two-wavelength interferometry. The synthetic wavelength, Λ=c/∆ν, is highly stable and accurate, owing to the frequency stability of the locked lasers and the precise determination of the frequency difference Δν between Cs 2 and I 2 transitions. The dense spectra of these molecules allows selection of Λ over a wide range, between 8.5 mm and several meters, thus enabling distance measurements with a large non-ambiguity range. Fringe contrast and phase-shifting methods are used to measure the phase difference. An accuracy of 70 μm is achieved for Λ~19 mm, i.e. Λ/260.

High-frequency-stability diode-pumped Nd:YAG lasers with the FM sidebands method and Doppler-free iodine lines at 532 nm

1999 ◽  
Vol 38 (33) ◽  
pp. 6962 ◽  
Author(s):  
Gianluca Galzerano ◽  
Cesare Svelto ◽  
Elio Bava ◽  
Fabrizio Bertinetto
Keyword(s):  
High Frequency ◽  
Frequency Stability ◽  
Nd:Yag Lasers ◽  
Free Iodine ◽  
Diode Pumped ◽  
532 Nm

Atomic Absorption Methods for the Direct Analysis of Metals and Alloys

1973 ◽  
Vol 27 (5) ◽  
pp. 335-341 ◽  
Author(s):  
Alan Walsh
Keyword(s):  
Atomic Absorption ◽  
Direct Analysis ◽  
Precise Determination ◽  
Metals And Alloys ◽  
Spectrochemical Analysis ◽  
Solid Samples ◽  
Trace Impurities ◽  
Wide Range

While atomic absorption methods of spectrochemical analysis have found a wide range of application, they have been almost entirely confined to the analysis of solutions. Solid samples for analysis have required prior solution. In recent months the situation has been transformed, and it has been demonstrated that some important metals and alloys can be analyzed directly by atomic absorption methods, which can be applied to the precise determination of major constituents and of trace impurities.

The Application of Petroleum Geochemical Methods to Production Allocation of Commingled Fluids

2021 ◽  
Author(s):  
Richard Patience ◽  
Mark Bastow ◽  
Martin Fowler ◽  
Julian Moore ◽  
Craig Barrie
Keyword(s):  
Best Practice ◽  
Statistical Treatment ◽  
Laboratory Analysis ◽  
Chemical Compositions ◽  
Production Allocation ◽  
Wide Range ◽  
Operational Activity ◽  
End Members ◽  
Selection Of

Abstract Production allocation from petroleum geochemistry is defined here as the quantitative determination of the amount or portion of a commingled fluid to be assigned to two or more individual fluid sources (e.g., a pipeline, field, reservoir, well) at a particular moment in time, based on the fluid chemistry. It requires: i) knowledge of the original chemical compositions of each of the fluids prior to mixing (referred to here as the "end members"), and ii) that statistically valid differences in their chemistries can be identified. Petroleum geochemical-based methods for production monitoring and allocation are much lower cost than using production logging tools, as there is no additional rig time or extra personnel required at the well site. Additionally, no intervention to the production of hydrocarbons from a well is required and, hence, there is none of the risk entailed in additional operational activity. Geochemical methods are applicable to a wide range of fields, irrespective of pressure, temperature, reservoir quality and reservoir fluid type. The method has been in existence for over 30 years, during which time a number of different analytical methods, data pre-processing and treatment approaches have been applied. This paper summarises these approaches, and provides examples, but also describes a "best practice" which is not a "one size fits all" approach, as is sometimes seen in the literature. A successful production allocation study consists of the following steps: i) Selection of end member samples that contribute to the commingled production fluid; ii) Determination of the differences in chemical composition of the end members through laboratory analysis of the end members (e.g. by WO-GC), replicate analyses of samples and statistical treatment of the data (e.g. PCA); iii) If statistically significant differences exist, laboratory analysis of the end members and commingled fluids with appropriate replicate analyses of samples; iv) Data selection, pre-processing (e.g. selection of ratios or concentrations of components); v) Determination of end member contributions by solving equations (e.g. least squares best fit) and uncertainty estimation (e.g. Monte Carlo or Bootstrap methods). The differences in approach for conventional versus unconventional plays are also discussed.

Chosen applications and approaches to modeling lasers in dentistry

2021 ◽  
pp. 2150329
Author(s):  
Vladan Mirjanić ◽  
Milesa Srećković ◽  
Ðorđe Mirjanić ◽  
Aleksandar Bugarinović ◽  
Dragan Druzijanić ◽  
...  
Keyword(s):  
Short Pulse ◽  
Precise Determination ◽  
Living Tissue ◽  
Software Support ◽  
Dental Tissues ◽  
Wide Range ◽  
Laser Techniques ◽  
Therapeutic Doses ◽  
Tooth Tissue

Historically, although the first indications for the use of lasers in general were in dentistry, coming as a relief from the sound of the drill and mechanical contacts, it still seems somewhat that the entry in various ways of lasers in dentistry has been slower. This is somewhat true for the situation at the continents (e.g. USA much later approved the application relative to Europe). This paper analyzes the potential and existing applications of lasers in dentistry in a wide range of existing types, including interaction with dental tissues, in terms of surgical applications, on living tissue, the prosthetic area of applications and therapeutic doses. There is another special feature that can be recognized is the precise determination of the color of the material (teeth and prosthetics) and in general the determination of the composition of the material including classic, but also modern laser techniques (LIBS, complimentary techniques, tooth tissue, bone) and especially in the case of the first Q switch systems related to pain reduction, because the short pulse favors the intervention rate (ns, ps and fs). Special attention should be paid to modeling of interaction and analysis with the appropriate software support.

scholarly journals Perancangan Aplikasi Tes IQ Siswa untuk Pertimbangan Pemilihan Jurusan dengan Metode Forward Chaining

2016 ◽  
Vol 3 (2) ◽  
pp. 102
Author(s):  
Ahyuna Ahyuna ◽  
Irmawati Irmawati
Keyword(s):  
Measuring Instruments ◽  
Measuring Devices ◽  
Iq Test ◽  
Wide Range ◽  
Computer Based ◽  
White Box Testing ◽  
Necessary Existence ◽  
Selection Of ◽  
Iq Tests

IQ merupakan pengelompokan kecerdasan manusia, untuk mengetahui kecerdasan seseorang berbagai macam alat ukur yang digunakan diantaranya adalah tes inteligensi, tes emosional, tes spiritual, psikotes dan alat ukur lainnya. Semakin tinggi semangat orang untuk meraih sukses, semakin tinggi pula kebutuhan akan modal intelektual, emosional, psikologis, minat dan bakat. Segala kemampuan tersebut bisa jadi merupakan bakat terpendam dalam diri yang belum tergali, ataupun bakat yang harus dimunculkan dengan berbagai latihan. Tes IQ dalam penentuan dan pertimbangan pemilihan jurusan pada sekolah biasanya dilakukan secara manual dan membutuhkan waktu yang cukup banyak untuk mengetahui hasil IQ dalam penentuan pemilihan jurusan, selain itu banyak peserta tes sulit memahami untuk menghitung hasil tes IQ karena cukup rumit sehingga untuk mempermudah pihak sekolah dalam melaksanakan tes IQ penentuan jurusan maka diperlukan adanya suatu aplikasi yang berbasis komputer dan untuk membangun aplikasi yang akan digunakan bahasa pemrograman serta metode pengujian white box. Hasil evaluasi terhadap aplikasi yang dibangun sangat membantu serta mempercepat pihak sekolah dalam penentuan jurusan dan tepat dalam penentuan jurusan siswa yang disesuaikan kemampuan mereka serta membudayakan pemakaian komputer di kalangan siswa.IQ is a grouping of human intelligence, to determine a person's intellect wide range of measuring instruments used include intelligence tests, tests of emotional, spiritual tests, psychological and other measuring devices. The higher the spirit of people to achieve success, the higher the need for intellectual capital, emotional, psychological, interests and talents. All these capabilities can be a hidden talent within untapped, or talent that should be raised with the various exercises. IQ tests in the determination and consideration of election department at school is usually done manually and requires considerable time to know the results of IQ in determining the selection of majors, besides many test-takers is difficult to understand to calculate the results of an IQ test because it is quite complicated so as to facilitate the school in IQ tests determining the department implement the necessary existence of a computer-based applications and to build applications that will use the programming language as well as white-box testing methods. Results of evaluation of the applications that are built very helpful as well as accelerate the schools in the determination of the exact majors and students majoring in determining adjusted their abilities and cultivate the use of computers among students.

scholarly journals Influence of Mie scattering on nanoparticles with different particle sizes and shapes: Photometry and analytical ultracentrifugation with absorption optics

2005 ◽  
Vol 70 (3) ◽  
pp. 361-369 ◽  
Author(s):  
M.D. Lechner
Keyword(s):  
Analytical Ultracentrifugation ◽  
Mie Scattering ◽  
Precise Determination ◽  
Core Shell ◽  
Particle Sizes ◽  
Wide Range ◽  
Photometric Measurements ◽  
Shell Particles ◽  
Reliable Methods

Nanoparticles are used in large quantities for very different applications. A precise determination of the diameter and the particle size distribution which is responsible for the application properties is therefore essential. Reliable methods for measuring the above mentioned quantities are photometric measurements and analytical ultracentrifugation with an UV optics detector. Both methods are ruled by the Mie effect, that is scattering and absorption of the particles as function of the diameter, the wavelength, and the shape of the particles. The extinction coefficients ?=?/c for spheres, rods, and core shell particles have been calculated and plotted over a wide range of the size parameter ?d/?. Two examples for multimodal latex particles and core shell particles have been given and demonstrate the applicability of the method.

Immunological and colorimetric determination of prostatic acid phosphatase--technical and clinical reappraisal in symptomatic patients.

1986 ◽  
Vol 32 (9) ◽  
pp. 1760-1766 ◽  
Author(s):  
I Gibb ◽  
L A Wilson ◽  
P H Powell ◽  
I Tarbit ◽  
D Pratt ◽  
...  
Keyword(s):  
Differential Diagnosis ◽  
Acid Phosphatase ◽  
Prostatic Carcinoma ◽  
Prostatic Acid Phosphatase ◽  
Immunological Methods ◽  
Colorimetric Determination ◽  
Nitrophenyl Phosphate ◽  
Wide Range ◽  
Selection Of

Abstract We compared a selection of quantitative immunological methods for prostatic acid phosphatase (PAP) with routine colorimetric assays for total and tartrate-labile acid phosphatase and evaluated their relative clinical merits in the differential diagnosis of prostatic carcinoma. We also assessed a wide range of commercial control materials for suitability of use with these methods. Patients studied included 111 cases of prostatic carcinoma, 42 cases of benign prostatic hyperplasia, and 33 controls. The principles of the methods used included determination of enzymatic activity using p-nitrophenyl phosphate, RIA, immunoradiometric, and enzymoimmunometric assays. Performance characteristics for the immunological methods were inferior to manufacturers' precision and specificity claims. We identified control materials that were unsuitable for routine use. Poor discrimination between clinical groups was observed for all methods. Analysis by use of a receiver operator characteristic plot failed to improve this. We conclude that the immunological methods we studied offer no advantages over colorimetric methods in the differential diagnosis of prostatic cancer in symptomatic patients.

Estimation of the performance stability of the newly developed topical haemostatic agents based on the chitosan/alginate fibrids

2016 ◽  
Vol 87 (7) ◽  
pp. 780-789 ◽  
Author(s):  
Marcin H Struszczyk ◽  
Bożena Wilbik-Hałgas ◽  
Michał Miklas ◽  
Magdalena Cichecka ◽  
Magdalena Kucharska ◽  
...  
Keyword(s):  
Medical Devices ◽  
Raw Materials ◽  
Testing Methods ◽  
Testing Method ◽  
Haemostatic Agents ◽  
Wide Range ◽  
The Stability ◽  
Preclinical And Clinical Studies ◽  
Selection Of

Designing medical devices requires a wide range of verification steps for estimation of the performance and safety. Designing the research program needs a rational selection of appropriate testing methods (in preclinical and clinical studies) for determination of the risk of potential incompatibilities resulting in adverse events. The significance of the appropriate selection of the testing method is increased in advanced medical devices. The presented research considers the verification of the functional properties of recently developed topical haemostatic agents with the use of the chitosan/alginate fibrids, based on the previously elaborated risk analysis made according to the guidelines of the PN-EN-ISO 14971:2012 and PN-EN ISO 22442-1:2008 standards. The aim of this research was to verify the stability of the performance of the newly developed haemostatic agents during storage. The defined aim of the study arose from the thesis that the appropriate selection of raw materials and a new manner of reprocessing them enabled keeping the usability of the final product for at least two years.

scholarly journals Specifics of Determination of Human Biological Age by Blood Samples Using Epigenetic Markers

2021 ◽  
Author(s):  
Viachaslau Kipen ◽  
Maryna Bahdanava ◽  
Aryna Burakova ◽  
Olga Dobysh ◽  
Olga Zotova ◽  
...  
Keyword(s):  
Chronic Diseases ◽  
Information Content ◽  
Critical Role ◽  
Healthy Person ◽  
Test System ◽  
Precise Determination ◽  
Biological Age ◽  
Genome Wide ◽  
Selection Of

Abstract Our research focused on the selection of already known markers, as well as the search for other infonormative markers based on data made publicly available on the GEO NCBI platform (genome-wide DNA methylation projects using the Infinium Human Methylation 450K BeadChip (Illumina ©)). The main objective of the study was to demonstrate that the accuracy of determining the biological age of a person in the presence of chronic diseases using linear-dependent methylation markers is comparable to the accuracy of determining the biological age of a healthy person. Criminologists, as a rule, do not have information about the chronic diseases of a person who has left a biological trace at the scene (blood, for example). However, the lack of this information, as we have shown for a some of diseases, does not play a critical role in the precise determination of biological age. Additionally, an obstacle was removed when transferring the information content of markers from Infinium Human Methylation 450K BeadChip chips to SNaPshot technology. The analysis was carried out on a sample of 236 Belarusians, for whom the methylation profile for 7 Cpg markers is presented. It is shown that the information content of markers is preserved Our analysis shows the possibility of creating the universal test system for predicting biological age according to marker methylation. The system can be used in the work of the most criminalist in the world with the same task.

IMPROVEMENT OF SAMPLE PREPARATION IN ICP-AES ANALYSIS OF FERROALLOYS

2019 ◽  
Vol 85 (5) ◽  
pp. 11-17
Author(s):  
I. I. Chernikova ◽  
K. Y. Tumneva ◽  
T. Y. Bakaldina ◽  
T. N. Ermolaeva
Keyword(s):  
Sample Preparation ◽  
Internal Standard ◽  
Analytical Signal ◽  
Precise Determination ◽  
Standard Samples ◽  
Microwave Sample Preparation ◽  
Wide Range ◽  
Significant Difference ◽  
Temperature Time

A set of ICP-AES techniques has been developed for determination of rated elements: Ti, Si, R Al, Cu, Mo, V, Sn, and Zr in ferrotitanium; Ni, Fe, Cu, Co, and As in ferronickel; Si, Cr, and P in ferrochrome silicon; Zr, Si, Al, R and Cu in zirconium ferrosilicon; Mn, Si, and P in manganese ferrosilicon. Combination of the multi-element ICP-AES method which allows precise determination of the elements in ferroalloys in a wide range of concentrations and microwave sample preparation in closed autoclaves which excludes the loss of the components to be determined provides the rapidity of the analysis procedure. The composition of solutions for opening samples of ferroalloys and temperature-time modes of microwave sample preparation in an autoclave are substantiated. Conditions for ICP-AES determination of the rated elements in ferroalloys are studied. Analytical lines of the elements to be determined free from significant spectral overlaps are chosen. The dilution rates of the solutions are determined. The method of internal standard was used to improve the reproducibility of the analytical signal for Ti determination in ferrotitanium, Si and Cr in ferrochrome silicon, as well as all rated elements in manganese ferrosilicon and ferronickel. The spectrometer was calibrated using model solutions and solutions of standard samples added with the certified solutions of the elements to be determined. To determine Ti, Si, FJ Al, Cu, У and Zr in ferrotitanium; Ni, Fe, Cu, and Co in ferronickel; Si, Cr, and P in ferrochrome silicon; Zr, Si, Al, P, and Cu in zirconium ferrosilicon; Si and P in manganese ferrosilicon a multidimensional graduation by two analytical lines was used. The correctness of the determination was evaluated in analysis of standard samples of ferroalloys and comparative analysis of the obtained results with the data of standard methods: comparison of the variances according to the Fisher criterion did not reveal any significant difference between them, whereas the use of the modified Student test showed the absence of the systematic error.

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