We acknowledge the services of Stanley Flegler, Carol Flegler, and Abigail Tirrell at the MSU Center for Advanced Microscopy. We thank Ray Clark and Mark Wilson for technical assistance with the set-up of the electrochemical etching apparatus. Earlier contributions from Anne Benjamin, Georg Bollen, Rafael Ferrer, David Lincoln, Stefan Schwarz and Adrian Valverde, and technical assistance from John Yurkon are also acknowledged. This work was partially supported by the National Science Foundation contract no. PHY-1102511 and PHY-1307233, Michigan State University and the Facility for Rare Isotope Beams, and Central Michigan University.

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The authors have nothing to disclose.

وصفناها إجراءات مباشرة لحفر electrochemically حادة نقاط الانبعاثات الميدان (FEPS) في محلول هيدروكسيد الصوديوم، ولاختبار FEPS من تشغيلها في وضع انبعاث المجال. إجراء الحفر وصفها هو الاختلاف من تقنيات الحالية الإفلات من تقنية الصفيحة 7،8 والعائمة 9،10 تقنية طبقة. ومع ذلك?...

وقد استخدمت نصائح حادة أو نقاط طويل في تطبيقات المجهر، مثل مجهر أيوني (FIM) (1) والمجهر النفقي الماسح (STM) 2، ومجموعة من التقنيات لإنتاج نصائح حادة من مواد مختلفة وضعت 3. ويمكن أيضا أن هذه النصائح حادة أن تعمل كنقاط الانبعاثات الميدان (FEPS) عن طريق تطبيق الجهد العالي لهم، ويكون بمثابة مصدر شعاع الالكترون مريحة. تطبيق واحد من مثل المصدر إنتاج أيون عن طريق تأين تأثير الإلكترون (زعبيل). في محطة إثراء الوقود هو مفيد بشكل خاص في التطبيقات حيث التقلبات في درجات الحرارة التي تنتجها بواعث الحرارية غير مرغوب فيها. على سبيل المثال، إنتاج أيون عن طريق إعمار للصناعة الغاز خلفية أو بخار في درجة عالية من الدقة فخ بينينج 4،5. وهناك طريقة بسيطة لافتعال FEPS هو حفر electrochemically قضبان التنغستن في محلول هيدروكسيد الصوديوم (هيدروكسيد الصوديوم). هذه التقنية هي بسيطة نسبيا لتنفيذ معوقد تبين أن المعدات متواضعة وأن تكون قابلة للتكرار تماما وموثوق بها. ووصف عدد من الأساليب في الأدب ويستمر إدخال تحسينات على هذه التقنيات للمثول 6. نحن هنا تصف طريقة لالنقش الكهروكيميائية من النصائح التنغستن في محلول هيدروكسيد الصوديوم. أسلوبنا هو الاختلاف من الصفيحة الإفلات من تقنية 7،8 والعائمة 9،10 تقنية طبقة. مثل هاتين الطريقتين أنه تمكن من إنتاج اثنين من نصائح من إجراء الحفر واحد. ويظهر صورة للجهاز تجريبي لالحفر النصائح في الشكل 1. <img alt="شكل 1" src="/files/ftp_upload/54030/54030fig1.jpg" /> الشكل 1. جهاز الحفر. الصورة من جهاز التجريبية المستخدمة في الحفر الكهروكيميائية من قضبان التنغستن مع محلول هيدروكسيد الصوديوم. <a href="https://www.jove.com/files/ftp_upload/54030/54030fig1large.jpg" target="_blank">يرجى النقر</a>هنا لعرض نسخة أكبر من هذا الرقم. النقش الكهروكيميائية من التنغستن في قاعدة هيدروكسيد الصوديوم المائية يحدث من خلال عملية ذات مرحلتين. أولا، يتم تشكيل أكاسيد التنغستن وسيطة، والثانية، وهذه الأكاسيد غير قابلة للelectrochemically حل لتشكيل أنيون تنجستات القابلة للذوبان. وصفت هذه العملية، في شكل مبسط، من خلال ردود الفعل اثنين (1) W + 6OH - → WO 3 (S) + 3H 2 O + 6E -، و (2) WO 3 (S) + 2OH - → WO 4 2- + H 2 O. التيار الحفر والحل المولية هيدروكسيد الصوديوم المستخدمة تؤثر على الوقت والجهد المطلوب لحفر من خلال قضيب التنغستن. وتقدم دراسات من هذه الآثار ومناقشتها. الأهم من ذلك، المعلمات النقش يكون لها تأثير على هندسة من النصائح، وعلى هذا النحو، على عملها في وضع انبعاث المجال. الهندسة لل<html> وتميزت نصائح أنتجنا عن طريق التصوير لهم المجهر الإلكتروني الماسح (SEM). هذه الصور يمكن أن تستخدم لتقدير، على سبيل المثال، في دائرة نصف قطرها طرف. وبالإضافة إلى ذلك، كانت تعمل النصائح في وضع انبعاث المجال من خلال تطبيق الجهد السلبي للعادة بضع مئات من فولت إلى بضعة كيلو فولت لهم ورصد مما أدى انبعاث الإلكترون الحالية. العلاقة بين تيار الانبعاث المجال، وأنا، والتطبيقية الجهد التحيز، والخامس، ويمكن وصف هذه المعادلة فاولر-نوردهايم 11 (3) I = AV 2 ه -Cr ممثل المؤسسة / V، حيث r ممثل المؤسسة هي دائرة نصف قطرها الفعلي لطرف، وغير ثابت، وC هو الثاني فاولر-نوردهايم ثابت <img alt="المعادلة 9" src="/files/ftp_upload/54030/54030eq9.jpg" /> ، الذي ب = 6.83 فولت - 3/2 V / نانومتر،030eq11.jpg &quot;/&gt; هي وظيفة عمل من التنغستن ( <img alt="معادلة 11" src="/files/ftp_upload/54030/54030eq11.jpg" /> ≈ 4.5 فولت)، ك هو أحد العوامل التي تعتمد على هندسة (ك ≈ 5)، و <img alt="معادلة 12" src="/files/ftp_upload/54030/54030eq15.jpg" /> هو مصطلح نوردهايم تصحيح الصورة ( <img alt="معادلة 12" src="/files/ftp_upload/54030/54030eq15.jpg" /> ≈ 1) 12. وبالتالي، فإن نصف قطر الفعال للطرف يمكن تحديد ذلك عن طريق قياس التيار الإلكترون بوصفها وظيفة من الجهد التحيز. على وجه التحديد، ويمكن الحصول عليها من منحدر ما يسمى فاولر-نوردهايم (FN) مؤامرة من قانون الجنسية (I / V 2) ضد 1 / V.

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			<td height="20" style="height:20px;width:325px;">Tungsten Rod 0.020&#34; x 12&#34;</td>
			<td style="width:159px;">ESPI Metals</td>
			<td style="width:451px;"><a href="http://www.espimetals.com/index.php/online-catalog/467-Tungsten">http://www.espimetals.com/index.php/online-catalog/467-Tungsten&#160;</a></td>
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			<td>Cole-Parmer</td>
			<td>Item # WU-88404-71</td>
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			<td>Cole-Parmer</td>
			<td>Item#&#160;WU-34506-03</td>
			<td>250 mL&#160;</td>
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			<td height="20" style="height:20px;">DC Power supply</td>
			<td>BK Precision</td>
			<td>1672</td>
			<td>Triple Output 0 - 32 V, 0 - 3 A DC Power Supply</td>
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electrochemical etching and characterization of sharp field emission points for electron impact ionization

A new variation of the drop-off method for fabricating field emission points by electrochemically etching tungsten rods in a NaOH solution is described. The results of studies in which the etching current and the molarity of the NaOH solution used in the etching process were varied are presented. The investigation of the geometry of the tips, by imaging them with a scanning electron microscope, and by operating them in field emission mode is also described. The field emission tips produced are intended to be used as an electron beam source for ion production via electron impact ionization of background gas or vapor in Penning trap mass spectrometry applications.

دراسة المعلمات الحفر أثناء عملية الحفر يتم تشغيل التيار الكهربائي في الوضع الحالي مستمر. الجهد المطلوب للحفاظ على هذه الزيادات الحالية مستمرة قليلا كما هو محفورا قضيب التنغستن بعيدا...

Watch this Scientific Journal Video about Electrochemical Etching and Characterization of Sharp Field Emission Points for Electron Impact Ionization at JoVE.com

Electrochemical Etching and Characterization of Sharp Field Emission Points for Electron Impact Ionization

A method for electrochemically etching field emission tips is presented. Etching parameters are characterized and the operation of the tips in field emission mode is investigated.

الكهروكيميائية النقش وتوصيف نقاط شارب الميدان الانبعاثات الكترون تأثير التأين

A new variation of the drop-off method for fabricating field emission points by electrochemically etching tungsten rods in a NaOH solution is described. ...

electrochemical-etching-characterization-sharp-field-emission-points

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9.4K Views.  Central Michigan University. A method for electrochemically etching field emission tips is presented. Etching parameters are characterized and the operation of the tips in field emission mode is investigated.

Video: Electrochemical Etching and Characterization of Sharp Field Emission Points for Electron Impact Ionization

Fabrication of VB2/Air Cells for Electrochemical Testing

A technique to investigate the properties and performance of new multi-electron metal/air battery systems is proposed and presented. A method for synthesizing nanoscopic VB2 is presented as well as step-by-step procedure for applying a zirconium oxide coating to the VB2 particles for stabilization upon discharge. The process for disassembling existing zinc/air cells is shown, in addition construction of the new working electrode to replace the conventional zinc/air cell anode with a the nanoscopic VB2 anode. Finally, discharge of the completed VB2/air battery is reported. We show that using the zinc/air cell as a test bed is useful to provide a consistent configuration to study the performance of the high-energy high capacity nanoscopic VB2 anode.

Fabrication of VB2/Air Cells for Electrochemical Testing

A protocol is presented to study multi-electron metal/air battery systems by using previous technology developed for the zinc/air cell. Electrochemical testing is then performed on fabricated batteries to evaluate performance.

تلفيق من VB<sub&gt; 2</sub&gt; / الخلايا الكهروكيميائية الهواء للاختبار

A technique to investigate the properties and performance of new multi-electron metal/air battery systems is proposed and presented. A method for ...

Spatial Separation of Molecular Conformers and Clusters

Gas-phase molecular physics and physical chemistry experiments commonly use supersonic expansions through pulsed valves for the production of cold molecular beams. However, these beams often contain multiple conformers and clusters, even at low rotational temperatures. We present an experimental methodology that allows the spatial separation of these constituent parts of a molecular beam expansion. Using an electric deflector the beam is separated by its mass-to-dipole moment ratio, analogous to a bender or an electric sector mass spectrometer spatially dispersing charged molecules on the basis of their mass-to-charge ratio. This deflector exploits the Stark effect in an inhomogeneous electric field and allows the separation of individual species of polar neutral molecules and clusters. It furthermore allows the selection of the coldest part of a molecular beam, as low-energy rotational quantum states generally experience the largest deflection. Different structural isomers (conformers) of a species can be separated due to the different arrangement of functional groups, which leads to distinct dipole moments. These are exploited by the electrostatic deflector for the production of a conformationally pure sample from a molecular beam. Similarly, specific cluster stoichiometries can be selected, as the mass and dipole moment of a given cluster depends on the degree of solvation around the parent molecule. This allows experiments on specific cluster sizes and structures, enabling the systematic study of solvation of neutral molecules.

We present a technique that allows the spatial separation of different conformers or clusters present in a molecular beam. An electrostatic deflector is used to separate species by their mass-to-dipole moment ratio, leading to the production of gas-phase ensembles of a single conformer or cluster stoichiometry.

الفصل المكاني للمتشكلات الجزيئية والتجمعات

Gas-phase molecular physics and physical chemistry experiments commonly use supersonic expansions through pulsed valves for the production of cold ...

Characterization of Recombination Effects in a Liquid Ionization Chamber Used for the Dosimetry of a Radiosurgical Accelerator

Most modern radiation therapy devices allow the use of very small fields, either through beamlets in Intensity-Modulated Radiation Therapy (IMRT) or via stereotactic radiotherapy where positioning accuracy allows delivering very high doses per fraction in a small volume of the patient. Dosimetric measurements on medical accelerators are conventionally realized using air-filled ionization chambers. However, in small beams these are subject to nonnegligible perturbation effects. This study focuses on liquid ionization chambers, which offer advantages in terms of spatial resolution and low fluence perturbation. Ion recombination effects are investigated for the microLion detector (PTW) used with the Cyberknife system (Accuray). The method consists of performing a series of water tank measurements at different source-surface distances, and applying corrections to the liquid detector readings based on simultaneous gaseous detector measurements. This approach facilitates isolating the recombination effects arising from the high density of the liquid sensitive medium and obtaining correction factors to apply to the detector readings. The main difficulty resides in achieving a sufficient level of accuracy in the setup to be able to detect small changes in the chamber response.

A growing number of radiation therapy devices offer the advantage of delivering the dose through very small beams to the tumor, allowing for increased conformity and higher doses per fraction. Many different detectors can be used for the dosimetry of these small fields. In the present study, the effect of ion recombination is investigated for a liquid ionization chamber using a stereotactic radiation therapy system.

توصيف التوحد آثار في غرفة التأين السائل المستخدمة لقياس الجرعات الإشعاعية من مسرع مبضع

Most modern radiation therapy devices allow the use of very small fields, either through beamlets in Intensity-Modulated Radiation Therapy (IMRT) or via ...

Electron Channeling Contrast Imaging for Rapid III-V Heteroepitaxial Characterization

Misfit dislocations in heteroepitaxial layers of GaP grown on Si(001) substrates are characterized through use of electron channeling contrast imaging (ECCI) in a scanning electron microscope (SEM). ECCI allows for imaging of defects and crystallographic features under specific diffraction conditions, similar to that possible via plan-view transmission electron microscopy (PV-TEM). A particular advantage of the ECCI technique is that it requires little to no sample preparation, and indeed can use large area, as-produced samples, making it a considerably higher throughput characterization method than TEM. Similar to TEM, different diffraction conditions can be obtained with ECCI by tilting and rotating the sample in the SEM. This capability enables the selective imaging of specific defects, such as misfit dislocations at the GaP/Si interface, with high contrast levels, which are determined by the standard invisibility criteria. An example application of this technique is described wherein ECCI imaging is used to determine the critical thickness for dislocation nucleation for GaP-on-Si by imaging a range of samples with various GaP epilayer thicknesses. Examples of ECCI micrographs of additional defect types, including threading dislocations and a stacking fault, are provided as demonstration of its broad, TEM-like applicability. Ultimately, the combination of TEM-like capabilities &#8211; high spatial resolution and richness of microstructural data &#8211; with the convenience and speed of SEM, position ECCI as a powerful tool for the rapid characterization of crystalline materials.

The use of electron channeling contrast imaging in a scanning electron microscope to characterize defects in III-V/Si heteroexpitaxial thin films is described. This method yields similar results to plan-view transmission electron microscopy, but in significantly less time due to lack of required sample preparation.

الإلكترون توجيه التباين التصوير لرابيد III-V Heteroepitaxial توصيف

Misfit dislocations in heteroepitaxial layers of GaP grown on Si(001) substrates are characterized through use of electron channeling contrast imaging ...

Protocol of Electrochemical Test and Characterization of Aprotic Li-O2 Battery

We demonstrate a method for electrochemical testing of an aprotic Li-O2 battery. An aprotic Li-O2 battery is made of a Li-metal anode, an aprotic electrolyte, and an O2-breathing cathode. The aprotic electrolyte is a solution of lithium salt with aprotic solvent; and porous carbon is commonly used as the cathode substrate. To improve the performance, an electrocatalyst is deposited onto the porous carbon substrate by certain deposition methods, such as atomic layer deposition (ALD) and wet-chemistry reaction. The as-prepared cathode materials are characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray absorption near edge structure (XANES). A Swagelok-type cell, sealed in a glass chamber filled with pure O2, is used for the electrochemical test on a battery test system. The cells are tested under either capacity-controlled mode or voltage controlled mode. The reaction products are investigated by electron microscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, and Raman spectroscopy to study the possible pathway of oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). This protocol demonstrates a systematic and efficient arrangement of routine tests of the aprotic Li-O2 battery, including the electrochemical test and characterization of battery materials.

Protocol of Electrochemical Test and Characterization of Aprotic Li-O2 Battery

A protocol for the electrochemical testing of an aprotic Li-O2 battery with the preparation of electrodes and electrolytes and an introduction of the frequently used methods of characterization is presented here.

بروتوكول الكهروكيميائية اختبار وتوصيف ابروتوني لي-O<sub&gt; 2</sub&gt; البطارية

We demonstrate a method for electrochemical testing of an aprotic Li-O2 battery. An aprotic Li-O2 battery is made of a Li-metal anode, an aprotic ...

Emission Spectroscopic Boundary Layer Investigation during Ablative Material Testing in Plasmatron

Ablative Thermal Protection Systems (TPS) allowed the first humans to safely return to Earth from the moon and are still considered as the only solution for future high-speed reentry missions. But despite the advancements made since Apollo, heat flux prediction remains an imperfect science and engineers resort to safety factors to determine the TPS thickness. This goes at the expense of embarked payload, hampering, for example, sample return missions. 
Ground testing in plasma wind-tunnels is currently the only affordable possibility for both material qualification and validation of material response codes. The subsonic 1.2MW Inductively Coupled Plasmatron facility at the von Karman Institute for Fluid Dynamics is able to reproduce a wide range of reentry environments. This protocol describes a procedure for the study of the gas/surface interaction on ablative materials in high enthalpy flows and presents sample results of a non-pyrolyzing, ablating carbon fiber precursor. With this publication, the authors envisage the definition of a standard procedure, facilitating comparison with other laboratories and contributing to ongoing efforts to improve heat shield reliability and reduce design uncertainties.
The described core techniques are non-intrusive methods to track the material recession with a high-speed camera along with the chemistry in the reactive boundary layer, probed by emission spectroscopy. Although optical emission spectroscopy is limited to line-of-sight measurements and is further constrained to electronically excited atoms and molecules, its simplicity and broad applicability still make it the technique of choice for analysis of the reactive boundary layer. Recession of the ablating sample further requires that the distance of the measurement location with respect to the surface is known at all times during the experiment. Calibration of the optical system of the applied three spectrometers allowed quantitative comparison. At the fiber scale, results from a post-test microscopy analysis are presented.

Development of new ablative materials and their numerical modeling requires extensive experimental investigation. This protocol describes procedures for material response characterization in plasma flows with the core techniques being non-intrusive methods to track the material recession along with the chemistry in the reactive boundary layer by emission spectroscopy.

الانبعاثات الطيفية الحدود التحقيق طبقة خلال صيغة الجر اختبار المواد في Plasmatron

Ablative Thermal Protection Systems (TPS) allowed the first humans to safely return to Earth from the moon and are still considered as the only solution ...

Comprehensive Characterization of Extended Defects in Semiconductor Materials by a Scanning Electron Microscope

Extended defects such as dislocations and grain boundaries have a strong influence on the performance of microelectronic devices and on other applications of semiconductor materials. However, it is still under debate how the defect structure determines the band structure, and therefore, the recombination behavior of electron-hole pairs responsible for the optical and electrical properties of the extended defects. The present paper is a survey of procedures for the spatially resolved investigation of structural and of physical properties of extended defects in semiconductor materials with a scanning electron microscope (SEM). Representative examples are given for crystalline silicon. The luminescence behavior of extended defects can be investigated by cathodoluminescence (CL) measurements. They are particularly valuable because spectrally and spatially resolved information can be obtained simultaneously. For silicon, with an indirect electronic band structure, CL measurements should be carried out at low temperatures down to 5 K due to the low fraction of radiative recombination processes in comparison to non-radiative transitions at room temperature. For the study of the electrical properties of extended defects, the electron beam induced current (EBIC) technique can be applied. The EBIC image reflects the local distribution of defects due to the increased charge-carrier recombination in their vicinity. The procedure for EBIC investigations is described for measurements at room temperature and at low temperatures. Internal strain fields arising from extended defects can be determined quantitatively by cross-correlation electron backscatter diffraction (ccEBSD). This method is challenging because of the necessary preparation of the sample surface and because of the quality of the diffraction patterns which are recorded during the mapping of the sample. The spatial resolution of the three experimental techniques is compared.

The optical, electrical, and structural properties of dislocations and of grain boundaries in semiconductor materials can be determined by experiments performed in a scanning electron microscope. Electron microscopy has been used to investigate cathodoluminescence, electron beam induced current, and diffraction of backscattered electrons.

توصيف شامل العيوب الممتدة في المواد أشباه الموصلات من خلال مجهر المسح الإلكتروني

Extended defects such as dislocations and grain boundaries have a strong influence on the performance of microelectronic devices and on other applications ...

Fabrication of White Light-emitting Electrochemical Cells with Stable Emission from Exciplexes

The authors present an approach for fabricating stable white light emission from polymer light-emitting electrochemical cells (PLECs) having an active layer which consists of blue-fluorescent poly(9,9-di-n-dodecylfluorenyl-2,7-diyl) (PFD) and &#960;-conjugated triphenylamine molecules. This white light emission originates from exciplexes formed between PFD and amines in electronically excited states. A device containing PFD, 4,4&#39;,4&#39;&#39;-tris[2-naphthyl(phenyl)amino]triphenylamine (2-TNATA), Poly(ethylene oxide) and K2CF3SO3 showed white light emission with Commission internationale de l&#39;&#233;clairage (CIE) coordinates of (0.33, 0.43) and a Color Rendering Index (CRI) of Ra = 73 at an applied voltage of 3.5 V. Constant voltage measurements showed that the CIE coordinates of (0.27, 0.37), Ra of 67, and the emission color observed immediately after application of a voltage of 5 V were nearly unchanged and stable after 300 sec.

The authors present a method for fabricating stable white-light-emitting electrochemical cells utilizing emission from exciplexes formed between a blue-emitting fluorene polymer and aromatic amines.

تصنيع الأبيض التي ينبعث منها ضوء الخلايا الكهروكيميائية مع الانبعاثات مستقرة من Exciplexes

The authors present an approach for fabricating stable white light emission from polymer light-emitting electrochemical cells (PLECs) having an active ...

One-Step Approach to Fabricating Polydimethylsiloxane Microfluidic Channels of Different Geometric Sections by Sequential Wet Etching Processes

Polydimethylsiloxane (PDMS) materials are substantially exploited to fabricate microfluidic devices by using soft lithography replica molding techniques. Customized channel layout designs are necessary for specific functions and integrated performance of microfluidic devices in numerous biomedical and chemical applications (e.g., cell culture, biosensing, chemical synthesis, and liquid handling). Owing to the nature of molding approaches using silicon wafers with photoresist layers patterned by photolithography as master molds, the microfluidic channels commonly have regular cross sections of rectangular shapes with identical heights. Typically, channels with multiple heights or different geometric sections are designed to possess particular functions and to perform in various microfluidic applications (e.g., hydrophoresis is used for sorting particles and in continuous flows for separating blood cells6,7,8,9). Therefore, a great deal of effort has been made in constructing channels with various sections through multiple-step approaches like photolithography using several photoresist layers and assembly of different PDMS thin sheets. Nevertheless, such multiple-step approaches usually involve tedious procedures and extensive instrumentation. Furthermore, the fabricated devices may not perform consistently and the resulted experimental data may be unpredictable. Here, a one-step approach is developed for the straightforward fabrication of microfluidic channels with different geometric cross sections through PDMS sequential wet etching processes, that introduces etchant into channels of planned single-layer layouts embedded in PDMS materials. Compared to the existing methods for manufacturing PDMS microfluidic channels with different geometries, the developed one-step approach can significantly simplify the process to fabricate channels with non-rectangular sections or various heights. Consequently, the technique is a way of constructing complex microfluidic channels, which provides a fabrication solution for the advancement of innovative microfluidic systems.

Several methods are available for the fabrication of channels of non-rectangular sections embedded in polydimethylsiloxane microfluidic devices. Most of them involve multistep manufacturing and extensive alignment. In this paper, a one-step approach is reported for fabricating microfluidic channels of different geometric cross sections by polydimethylsiloxane sequential wet etching.

النهج خطوة واحدة إلى اختﻻق بولي دايمثيل سيلوكسان موائع جزيئية القنوات الأقسام الهندسية المختلفة بعمليات الحفر الرطب متسلسلة

Polydimethylsiloxane (PDMS) materials are substantially exploited to fabricate microfluidic devices by using soft lithography replica molding techniques. ...

Method Development for Contactless Resonant Cavity Dielectric Spectroscopic Studies of Cellulosic Paper

The current analytical techniques for characterizing printing and graphic arts substrates are largely ex situ and destructive. This limits the amount of data that can be obtained from an individual sample and renders it difficult to produce statistically relevant data for unique and rare materials. Resonant cavity dielectric spectroscopy is a non-destructive, contactless technique which can simultaneously interrogate both sides of a sheeted material and provide measurements which are suitable for statistical interpretations. This offers analysts the ability to quickly discriminate between sheeted materials based on composition and storage history. In this methodology article, we demonstrate how contactless resonant cavity dielectric spectroscopy may be used to differentiate between paper analytes of varying fiber species compositions, to determine the relative age of the paper, and to detect and quantify the amount of post-consumer waste (PCW) recycled fiber content in manufactured office paper.

A protocol for the non-destructive analysis of the fiber content and relative age of paper.

تطوير الأسلوب للحصول علي تماس الرنانة تجويف الرنين عازله الدراسات الطيفية للورق السليوليك

The current analytical techniques for characterizing printing and graphic arts substrates are largely ex situ and destructive. This limits the amount of ...