The authors have no acknowledgments.

1. Design
<ol>
	<li>See Figure 1 for details of the development drawing.</li>
	<li>Cut a 3-mm thick acrylic board to 210 mm in width x 60 mm in height x 104 mm in depth, bond with acrylic adhesive and assemble the case.</li>
	<li>Install as many as 30 optical cells of 12.5 x 12.5 mm.</li>
	<li>Attach switches and lamps for starting and stopping and a variable dial for the drying time setting on the front face of the casing.</li>
	<li>See Figure 2 for an external view and component configuration.</li>
	<li>Use acrylic and nylon for the casing and net, respectively. Fix the net to the frame and attach it to the upper part of the case.</li>
	<li>Use acrylic for the lattice of the optical-cell installation. Attach it to the top of the net.</li>
	<li>Mount the blowers to the back of the case.</li>
	<li>Use translucent acrylic for a waterdrop prevention partition.</li>
</ol>
2. Hardware Design Outline
<ol>
	<li>See Figure 3 for details of the circuit diagram.</li>
	<li>Step down from 12 V to 5 V by a three-terminal regulator for operating the microcomputer.</li>
	<li>Activate the blowers via an NPN transistor (25 V, 500 mA). 
	Note: Because the output pin of the microcomputer is 5 V.</li>
	<li>Control the rotation speed of the blowers by the pulse width modulation (PWM) operation of the output pin. 
	Note: The blower is being driven, the number of revolutions is controlled, and the strength is periodically changed.</li>
	<li>Connect the start push switch to the digital input pin.</li>
	<li>Connect the blowers&#8217; operation time setting volume to the analog input pin to change the voltage according to the rotational position.</li>
	<li>Connect the organic light-emitting diode (OLED) for the operation time display to the two digital output pins with an inter-integrated circuit (I2C).</li>
	<li>Connect the LED that lights up during the operation to the digital output pin.</li>
</ol>
3. Software Design Outline
<ol>
	<li>Use a microcomputer to control the blowers. 
	Note: The development environment was constructed using Arduino, which is one of the development environments called open-source hardware, and all circuits and software are open to the public.</li>
	<li>Outline of the operation
	<ol>
		<li>Press the start switch.</li>
		<li>Read the state of the button specified by the select button on the front and activate the blower according to that state.</li>
		<li>Read the drying time set by the variable resistor on the front as a voltage signal and start counting down the timer.</li>
		<li>Turn the LED lights up and display the remaining time on the OLED.</li>
	</ol>
	</li>
	<li>Detailed explanation
	<ol>
		<li>Read the volume position connected to the analog input pin as a voltage; then, it converts to the blower&#8217;s operation time and displays on the OLED.</li>
		<li>Detect the ON/OFF switch connected to J1-9, 10 pins of the circuit diagram when pressing the start switch, turn on the blowers&#8217; drive pin, activate the blowers, and turn on the LED during the operation.</li>
		<li>Control the blowers by PWM. Detect the position of the 10-k&#937; variable resistor connected to the circuit diagram J1-5, 6, 7, and drive the blowers with the corresponding output.</li>
		<li>Detect the position of the 10-k&#937; variable resistor connected to the circuit diagrams J1-1, 2, 3 pin by setting the drying time and activate the blowers for a time corresponding to that.</li>
		<li>Connect the power LED to the circuit diagrams J1-15, 16 pin. Connect the start LED to the circuit diagrams J1 - 12, 13. 
		Note: The power LED lights up when the power turns on, and the start LED lights up while the blowers are activated.</li>
		<li>Connect the OLED to PB4, PB5 of the CPU with an I2C. 
		Note: The operation time displayed on the OLED is counted down every second. When the operation time reaches 0, the blowers&#8217; drive pin is set to 0, the blowers are stopped, and the operating LED is turned off to make the transition to the initial standby state.</li>
		<li>Use the Adafruit SSD1306 library for an OLED display of Arduino. 
		Note: When the power switch is turned ON, operate in the order of initialization and message display. A part of the source code is shown below as an example of use of this library. 
		#include &#34;Wire.h&#34;; 
		#include &#60;Adafruit_SSD1306.h&#62; 
		#define OLED_RESET -1 
		Adafruit_SSD1306 display(OLED_RESET); 
		<img alt="Equation" src="/files/ftp_upload/58518/58518eq1.jpg" /> 
		<img alt="Equation" src="/files/ftp_upload/58518/58518eq1.jpg" /> 
		void setup() { 
		Serial.begin(115200); 
		while (!Serial) { 
		; // wait for serial port to connect. Needed for Leonardo only 
		} 
		Wire.begin(SDA, SCL); // (SDA, SCL) 
		delay(1000); 
		display.clearDisplay(); // Clear the buffer. 
		display.setTextSize(1); 
		display.clearDisplay(); 
		display.print(F(&#34;SD &#34;)); // Weake Up Message Display(Version) 
		display.println(ver); 
		display.display(); 
		<img alt="Equation" src="/files/ftp_upload/58518/58518eq1.jpg" /> 
		<img alt="Equation" src="/files/ftp_upload/58518/58518eq1.jpg" /> 
		}</li>
	</ol>
	</li>
</ol>
4. Method of Operation
<ol>
	<li>See Figure 2 for details of the External View.</li>
	<li>Turn the main power switch of number 10 ON. The operation lamp of number 11 lights up.</li>
	<li>Place the optical cells on the mesh number 2 from the lattice part of the plastic of number 1. 
	Note: The number of optical cells that can be mounted is as many as the number of lattices.</li>
	<li>Select a two-blower operation or four-blower operation. Depending on the driving situation, the operation lamp of number 5 and number 6 lights up. 
	Note: Number 3 is a switch for operating the blowers on the right side, and number 4 is a switch for operating the blowers on the left side.</li>
	<li>Set the operation time with the timer with number 9.</li>
	<li>Turn number 7 on. 
	Note: The fan with number 12 starts, and, at the same time, the operation lamp of number 8 lights up.</li>
</ol>
5. Method to Measure the Drying Time
<ol>
	<li>In the case of natural drying
	<ol>
		<li>Wash the optical cells thoroughly with water or ethanol. Use thick absorbent paper to absorb the moisture of the optical cells, then move the cells to another place on the thick absorbent paper and wait until they dry.</li>
	</ol>
	</li>
	<li>In the case of the optical-cell dryer
	<ol>
		<li>Wash the optical cells thoroughly with water or ethanol. 
		Note: Use thick absorbent paper to temporarily absorb the moisture.</li>
		<li>Place the optical cells in the optical-cell dryer, then wait until they are dry.</li>
		<li>Measure the drying time 3x for each cell.</li>
	</ol>
	</li>
	<li>Comparison of the average values 
	<ol>
		<li>Measure the drying times 3x at 30 places to obtain the distribution. 
		Note: This is to detect the time difference according to the position of the cells in the optical-cell dryer.</li>
		<li>Use average values of all 30 places for a comparison with water. 
		Note: In the case of washing with water, determine the positions of the optical cells randomly, then measure the drying time at 10 points.</li>
	</ol>
	</li>
</ol>

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The authors have nothing to disclose.

The optical cells can be dried simultaneously with the blowers, and the drying time can be considerably reduced. Even if the stop operation is not executed, it can be safely stopped by using the automatic stop function of the timer. From the measurement results of the drying time distribution, there was no significant difference in drying time because of the difference in the installation position of the optical cells.
A critical step of the protocol is the design of the casing. The challenge ...

Optical cells are used as laboratory instruments in a wide range of fields. In life science research, biomolecules such as nucleic acids and proteins are often utilized for experiments, and spectroscopic methods are widely used for quantitative methods. Accurately quantifying the sample of the experiment is indispensable for obtaining more accurate and reproducible results. The absorption spectrum obtained by a spectrophotometer has often been used for the quantification of biomolecules such as nucleic acids and proteins1,2,3,4. Research on oxidation-reduction characteristics caused by the change in the absorption spectrum and photoluminescence of a carbon nanotube (CNT) dispersed using DNA has also been conducted5,6,7,8,9,10. Optical cells are used for these measurements, but accurate measurements cannot be made unless they are thoroughly washed and dried.
When measuring absorption spectra or photoluminescence, it is impossible to measure precisely in dirty optical cells11,12,13,14,15. Economical disposable optical cells made of polystyrene and poly-methyl-methacrylate are also used to eliminate washing and contamination. However, when precise measurements are required, quartz glasses are often used, because they have extremely excellent optical properties such as light transmittance. In this case, the optical cells are washed after the measurement of the sample and repeatedly used. Usually, after washing optical cells with water or ethanol, they are dried naturally. When rapid drying is required, they are dried one by one by using hair dryers or similar equipment. Cleaning optical cells is one of the most unpleasant and time-consuming procedures in the experiment. As the number of samples increases, the drying time increases, which, in turn, increases the time required to conduct the experiment and research. In past studies, there have been no reports on peripheral devices of optical cells. This study aims to reduce the research time by drying multiple optical cells simultaneously.
We investigated whether other similar products exist. A box-type constant temperature dryer with a temperature control function and a timer function already exists; however, no commercial products with the same configuration can be found.
An outline of the production of this device is described. First, the box-type case is made using an acrylic plate. Nylon netting is attached to the top. A plastic grid is placed on it to fix the optical cell. The control circuit is stored inside the case, and the plastic plate is attached to protect the circuit from water droplets. The control circuit consists of a CPU and is controlled by software. Blowers are attached to the back of the case, and the wind supplied by the blowers enters the optical cells set upside down. The blowers are activated by a switch on the front, and they are automatically stopped by the timer. Depending on the number of optical cells to be dried, two or four blowers can be selected for operation. Water droplets dripping from the optical cells evaporate with the wind from the blowers. The quartz cells are washed with water or ethanol, and the drying time is compared with that of natural drying.

<table>
	<tbody>
		<tr>
			<td>blower</td>
			<td>ebm-papst</td>
			<td>422JN</td>
			<td>Mulfingen, Germany</td>
		</tr>
		<tr>
			<td>Microcomputer</td>
			<td>Atmel Corporation</td>
			<td>ATmega 328 P</td>
			<td>CA, USA</td>
		</tr>
		<tr>
			<td>Blower selection button</td>
			<td>Sengoku Densyo Co., Ltd.</td>
			<td>MS-358 (red)</td>
			<td>Tokyo, Japan</td>
		</tr>
		<tr>
			<td>Blower operationg lamp</td>
			<td>Akizuki Denshi Tsusho Co., Ltd.</td>
			<td>DB-15-T-OR</td>
			<td>Tokyo, Japan</td>
		</tr>
		<tr>
			<td>Blower start button</td>
			<td>Sengoku Densyo Co., Ltd.</td>
			<td>MS-350M (white)</td>
			<td>Tokyo, Japan</td>
		</tr>
		<tr>
			<td>Timer</td>
			<td>Akizuki Denshi Tsusho Co., Ltd.</td>
			<td>SH16K4A105L20KC</td>
			<td>Tokyo, Japan</td>
		</tr>
		<tr>
			<td>Power supply switch</td>
			<td>Marutsuelec Co., Ltd.</td>
			<td>3010-P3C1T1G2C01B02BKBK-EI</td>
			<td>Tokyo, Japan</td>
		</tr>
		<tr>
			<td>Power supply lamp</td>
			<td>Akizuki Denshi Tsusho Co., Ltd.</td>
			<td>DB-15-T-G</td>
			<td>Tokyo, Japan</td>
		</tr>
		<tr>
			<td>OLED module</td>
			<td>Akihabara Co., Ltd.</td>
			<td>M096P4W</td>
			<td>Tokyo, Japan</td>
		</tr>
	</tbody>
</table>

fabrication of an optical cell dryer for the spectroscopic analysis cells

Optical cells, which are experimental instruments, are small, square tubes sealed on one side. A sample is placed in this tube, and a measurement is performed with a spectroscope. The materials used for optical cells generally include quartz glass or plastic, but expensive quartz glass is reused by removing substances, other than liquids, to be analyzed that adhere to the interior of the container. In such a case, the optical cells are washed with water or ethanol and dried. Then, the next sample is added and measured. Optical cells are dried naturally or with a manual hairdryer. However, drying takes time, which makes it one of the factors that increase the experiment time. In this study, the objective is to drastically reduce the drying time with a dedicated automatic dryer that can dry multiple optical cells at once. To realize this, a circuit was designed for a microcomputer, and the hardware using it was independently designed and manufactured.

As shown in Table 1, in the case of ethanol washing, the average drying time in natural drying was 426.4 s, and the average drying time in the optical-cell dryer was 106 s. In the case of water washing, the average drying time in natural drying was 1481.4 s, and the average drying time in the optical-cell dryer was 371.6 s. In both cases, the drying time was reduced to approximately one-fourth. The drying time distribution of the optical-cell dryer is shown in <strong cla...

Watch this Scientific Journal Video about Fabrication of an Optical Cell Dryer for the Spectroscopic Analysis Cells at JoVE.com

Fabrication of an Optical Cell Dryer for the Spectroscopic Analysis Cells

A protocol for fabricating a device for simultaneously drying multiple optical cells is presented.

Optical cells, which are experimental instruments, are small, square tubes sealed on one side. A sample is placed in this tube, and a measurement is ...

fabrication-an-optical-cell-dryer-for-spectroscopic-analysis

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5.1K Views.  Tokyo University of Science. A protocol for fabricating a device for simultaneously drying multiple optical cells is presented.

Video: Fabrication of an Optical Cell Dryer for the Spectroscopic Analysis Cells

Construction and Testing of Coin Cells of Lithium Ion Batteries

Rechargeable lithium ion batteries have wide applications in electronics, where customers always demand more capacity and longer lifetime. Lithium ion batteries have also been considered to be used in electric and hybrid vehicles1 or even electrical grid stabilization systems2. All these applications simulate a dramatic increase in the research and development of battery materials3-7, including new materials3,8, doping9, nanostructuring10-13, coatings or surface modifications14-17 and novel binders18. Consequently, an increasing number of physicists, chemists and materials scientists have recently ventured into this area. Coin cells are widely used in research laboratories to test new battery materials; even for the research and development that target large-scale and high-power applications, small coin cells are often used to test the capacities and rate capabilities of new materials in the initial stage. 
 In 2010, we started a National Science Foundation (NSF) sponsored research project to investigate the surface adsorption and disordering in battery materials (grant no. DMR-1006515). In the initial stage of this project, we have struggled to learn the techniques of assembling and testing coin cells, which cannot be achieved without numerous help of other researchers in other universities (through frequent calls, email exchanges and two site visits). Thus, we feel that it is beneficial to document, by both text and video, a protocol of assembling and testing a coin cell, which will help other new researchers in this field. This effort represents the "Broader Impact" activities of our NSF project, and it will also help to educate and inspire students.
In this video article, we document a protocol to assemble a CR2032 coin cell with a LiCoO2 working electrode, a Li counter electrode, and (the mostly commonly used) polyvinylidene fluoride (PVDF) binder. To ensure new learners to readily repeat the protocol, we keep the protocol as specific and explicit as we can. However, it is important to note that in specific research and development work, many parameters adopted here can be varied. First, one can make coin cells of different sizes and test the working electrode against a counter electrode other than Li. Second, the amounts of C black and binder added into the working electrodes are often varied to suit the particular purpose of research; for example, large amounts of C black or even inert powder were added to the working electrode to test the "intrinsic" performance of cathode materials14. Third, better binders (other than PVDF) have also developed and used18. Finally, other types of electrolytes (instead of LiPF6) can also be used; in fact, certain high-voltage electrode materials will require the uses of special electrolytes7.

A protocol to construct and test coin cells of lithium ion batteries is described. The specific procedures of making a working electrode, preparing a counter electrode, assembling a cell inside a glovebox and testing the cell are presented.

Rechargeable lithium ion batteries have wide applications in electronics, where customers always demand more capacity and longer lifetime.  Lithium ion ...

Fabricating Metamaterials Using the Fiber Drawing Method

Metamaterials are man-made composite materials, fabricated by assembling components much smaller than the wavelength at which they operate 1. They owe their electromagnetic properties to the structure of their constituents, instead of the atoms that compose them. For example, sub-wavelength metal wires can be arranged to possess an effective electric permittivity that is either positive or negative at a given frequency, in contrast to the metals themselves 2. This unprecedented control over the behaviour of light can potentially lead to a number of novel devices, such as invisibility cloaks 3, negative refractive index materials 4, and lenses that resolve objects below the diffraction limit 5. However, metamaterials operating at optical, mid-infrared and terahertz frequencies are conventionally made using nano- and micro-fabrication techniques that are expensive and produce samples that are at most a few centimetres in size 6-7. Here we present a fabrication method to produce hundreds of meters of metal wire metamaterials in fiber form, which exhibit a terahertz plasmonic response 8. We combine the stack-and-draw technique used to produce microstructured polymer optical fiber 9 with the Taylor-wire process 10, using indium wires inside polymethylmethacrylate (PMMA) tubes. PMMA is chosen because it is an easy to handle, drawable dielectric with suitable optical properties in the terahertz region; indium because it has a melting temperature of 156.6 &deg;C which is appropriate for codrawing with PMMA. We include an indium wire of 1 mm diameter and 99.99% purity in a PMMA tube with 1 mm inner diameter (ID) and 12 mm outside diameter (OD) which is sealed at one end. The tube is evacuated and drawn down to an outer diameter of 1.2 mm. The resulting fiber is then cut into smaller pieces, and stacked into a larger PMMA tube. This stack is sealed at one end and fed into a furnace while being rapidly drawn, reducing the diameter of the structure by a factor of 10, and increasing the length by a factor of 100. Such fibers possess features on the micro- and nano- scale, are inherently flexible, mass-producible, and can be woven to exhibit electromagnetic properties that are not found in nature. They represent a promising platform for a number of novel devices from terahertz to optical frequencies, such as invisible fibers, woven negative refractive index cloths, and super-resolving lenses.

Metamaterials at terahertz frequencies offer unique opportunities, but are challenging to fabricate in bulk. We adapt the fabrication procedure for microstructured polymer optical fibers to inexpensively fabricate metamaterials potentially on an industrial scale. We produce polymethylmethacrylate fibers containing ~10 &mu;m diameter indium wires separated by ~100 &mu;m, which exhibit a terahertz plasmonic response.

Metamaterials are man-made composite materials, fabricated by assembling components much smaller than the wavelength at which they operate 1. They owe ...

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.

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

Fabrication and Characterization of Disordered Polymer Optical Fibers for Transverse Anderson Localization of Light

We develop and characterize a disordered polymer optical fiber that uses transverse Anderson localization as a novel waveguiding mechanism. The developed polymer optical fiber is composed of 80,000 strands of poly (methyl methacrylate) (PMMA) and polystyrene (PS) that are randomly mixed and drawn into a square cross section optical fiber with a side width of 250 &mu;m. Initially, each strand is 200 &mu;m in diameter and 8-inches long. During the mixing process of the original fiber strands, the fibers cross over each other; however, a large draw ratio guarantees that the refractive index profile is invariant along the length of the fiber for several tens of centimeters. The large refractive index difference of 0.1 between the disordered sites results in a small localized beam radius that is comparable to the beam radius of conventional optical fibers. The input light is launched from a standard single mode optical fiber using the butt-coupling method and the near-field output beam from the disordered fiber is imaged using a 40X objective and a CCD camera. The output beam diameter agrees well with the expected results from the numerical simulations. The disordered optical fiber presented in this work is the first device-level implementation of 2D Anderson localization, and can potentially be used for image transport and short-haul optical communication systems.

We develop and characterize a disordered polymer optical fiber that uses transverse Anderson localization as a novel waveguiding mechanism. This microstructured fiber can transport a small localized beam with a radius that is comparable to the beam radius of conventional optical fibers.

We develop and characterize a disordered polymer optical fiber that uses transverse Anderson localization as a novel waveguiding mechanism. The developed ...

Patterning via Optical Saturable Transitions - Fabrication and Characterization

This protocol describes the fabrication and characterization of nanostructures using a novel nanolithographic technique called Patterning via Optical Saturable Transitions (POST). In this technique the chemical properties of organic photochromic molecules that undergo single-photon reactions are exploited, enabling rapid top-down nanopatterning over large areas at low light intensities, thereby, allowing for the circumvention of the far-field diffraction barrier.4 Simple, cost-effective, high throughput and resolution alternatives to nanopatterning are being explored, such as, two-photon polymerization5,6, beam pen lithography (BPL)7, scanning electron beam lithography (SEBL), and focused ion beam (FIB) patterning. However, multi-photon approaches require high light intensities, which limit their potential for high throughput and offer low image contrast. Although, electron and ion beam lithographic processes offer increased resolution, the serial nature of the process is limited to slow writing speeds, which also prevents patterning of features over large areas. Beam-pen lithography is an approach towards parallel near-field optical lithography. However, the gap between the source of the beam and the surface of the photoresist needs to be controlled extremely precisely for good pattern uniformity and this is very challenging to accomplish for large arrays of beams. Patterning via Optical Saturable Transitions (POST) is an alternative optical nanopatterning technique for patterning sub-wavelength features1-3. Since this technique uses single photons instead of electrons, it is extremely fast and does not require high light intensities1-3, opening the door to massive parallelization.

We report that the diffraction limit of conventional optical lithography can be overcome by exploiting the transitions of organic photochromic derivatives induced by their photoisomerization at low light intensities.1-3 This paper outlines our fabrication technique and two locking mechanisms, namely: dissolution of one photoisomer and electrochemical oxidation.

This protocol describes the fabrication and characterization of nanostructures using a novel nanolithographic technique called Patterning via Optical ...

Fabrication and Operation of a Nano-Optical Conveyor Belt

The technique of using focused laser beams to trap and exert forces on small particles has enabled many pivotal discoveries in the nanoscale biological and physical sciences over the past few decades. The progress made in this field invites further study of even smaller systems and at a larger scale, with tools that could be distributed more easily and made more widely available. Unfortunately, the fundamental laws of diffraction limit the minimum size of the focal spot of a laser beam, which makes particles smaller than a half-wavelength in diameter hard to trap and generally prevents an operator from discriminating between particles which are closer together than one half-wavelength. This precludes the optical manipulation of many closely-spaced nanoparticles and&#160;limits the&#160;resolution of optical-mechanical systems. Furthermore, manipulation using focused beams requires beam-forming or steering optics, which can be very bulky and expensive. To address these limitations in the system scalability of conventional optical trapping our lab has devised an alternative technique which utilizes near-field optics to move particles across a chip. Instead of focusing laser beams in the far-field, the optical near field of plasmonic resonators produces the necessary local optical intensity enhancement to overcome the restrictions of diffraction and manipulate particles at higher resolution. Closely-spaced resonators produce strong optical traps which can be addressed to mediate the hand-off of particles from one to the next in a conveyor-belt-like fashion. Here, we describe how to design and produce a conveyor belt using a gold surface patterned with plasmonic C-shaped resonators and how to operate it with polarized laser light to achieve super-resolution nanoparticle manipulation and transport. The nano-optical conveyor belt chip can be produced using lithography techniques and easily packaged and distributed.

The scalability and resolution of conventional optical manipulation techniques are limited by diffraction. We circumvent the diffraction limit and describe a method of optically transporting nanoparticles across a chip using a gold surface patterned with a path of closely spaced C-shaped plasmonic resonators.

The technique of using focused laser beams to trap and exert forces on small particles has enabled many pivotal discoveries in the nanoscale biological ...

Quantification of Hydrogen Concentrations in Surface and Interface Layers and Bulk Materials through Depth Profiling with Nuclear Reaction Analysis

Nuclear reaction analysis (NRA) via the resonant 1H(15N,&#945;&#947;)12C reaction is a highly effective method of depth profiling that quantitatively and non-destructively reveals the hydrogen density distribution at surfaces, at interfaces, and in the volume of solid materials with high depth resolution. The technique applies a 15N ion beam of 6.385 MeV provided by an electrostatic accelerator and specifically detects the 1H isotope in depths up to about 2 &#956;m from the target surface. Surface H coverages are measured with a sensitivity in the order of ~1013 cm-2 (~1% of a typical atomic monolayer density) and H volume concentrations with a detection limit of ~1018 cm-3 (~100 at. ppm). The near-surface depth resolution is 2-5 nm for surface-normal 15N ion incidence onto the target and can be enhanced to values below 1 nm for very flat targets by adopting a surface-grazing incidence geometry. The method is versatile and readily applied to any high vacuum compatible homogeneous material with a smooth surface (no pores). Electrically conductive targets usually tolerate the ion beam irradiation with negligible degradation. Hydrogen quantitation and correct depth analysis require knowledge of the elementary composition (besides hydrogen) and mass density of the target material. Especially in combination with ultra-high vacuum methods for in-situ target preparation and characterization, 1H(15N,&#945;&#947;)12C NRA is ideally suited for hydrogen analysis at atomically controlled surfaces and nanostructured interfaces. We exemplarily demonstrate here the application of 15N NRA at the MALT Tandem accelerator facility of the University of Tokyo to (1) quantitatively measure the surface coverage and the bulk concentration of hydrogen in the near-surface region of a H2 exposed Pd(110) single crystal, and (2) to determine the depth location and layer density of hydrogen near the interfaces of thin SiO2 films on Si(100).

We illustrate the application of 1H(15N,&#945;&#947;)12C resonant nuclear reaction analysis (NRA) to quantitatively evaluate the density of hydrogen atoms on the surface, in the volume, and at an interfacial layer of solid materials. The near-surface hydrogen depth profiling of a Pd(110) single crystal and of SiO2/Si(100) stacks is described.

Nuclear reaction analysis (NRA) via the resonant 1H(15N,&#945;&#947;)12C reaction is a highly effective method of depth profiling that quantitatively and ...

Fabrication of Polymer Microspheres for Optical Resonator and Laser Applications

This paper describes three methods of preparing fluorescent microspheres comprising &#960;-conjugated or non-conjugated polymers: vapor diffusion, interface precipitation, and mini-emulsion. In all methods, well-defined, micrometer-sized spheres are obtained from a self-assembling process in solution. The vapor diffusion method can result in spheres with the highest sphericity and surface smoothness, yet the types of the polymers able to form these spheres are limited. On the other hand, in the mini-emulsion method, microspheres can be made from various types of polymers, even from highly crystalline polymers with coplanar, &#960;-conjugated backbones. The photoluminescent (PL) properties from single isolated microspheres are unusual: the PL is confined inside the spheres, propagates at the circumference of the spheres via the total internal reflection at the polymer/air interface, and self-interferes to show sharp and periodic resonant PL lines. These resonating modes are so-called "whispering gallery modes" (WGMs). This work demonstrates how to measure WGM PL from single isolated spheres using the micro-photoluminescence (&#181;-PL) technique. In this technique, a focused laser beam irradiates a single microsphere, and the luminescence is detected by a spectrometer. A micromanipulation technique is then used to connect the microspheres one by one and to demonstrate the intersphere PL propagation and color conversion from coupled microspheres upon excitation at the perimeter of one sphere and detection of PL from the other microsphere. These techniques, &#181;-PL and micromanipulation, are useful for experiments on micro-optic application using polymer materials.

Protocols for the synthesis of microspheres from polymers, the manipulation of microspheres, and micro-photoluminescence measurements are presented.

This paper describes three methods of preparing fluorescent microspheres comprising &#960;-conjugated or non-conjugated polymers: vapor diffusion, ...

Design and Fabrication of an Optical Fiber Made of Water

In this report, an optical fiber of which the core is made solely of water, while the cladding is air, is designed and manufactured. In contrast with solid-cladding devices, capillary oscillations are not restricted, allowing the fiber walls to move and vibrate. The fiber is constructed by a high direct current (DC) voltage of several thousand volts (kV) between two water reservoirs that creates a floating water thread, known as a water bridge. Through the choice of micropipettes, it is possible to control the maximal diameter and length of the fiber. Optical fiber couplers, at both sides of the bridge, activate it as an optical waveguide, allowing researchers to monitor the water fiber capillary body waves through transmission modulation and, therefore, deducing changes in surface tension.
Co-confining two important wave types, capillary and electromagnetic, opens a new path of research in the interactions between light and liquid-wall devices. Water-walled microdevices are a million times softer than their solid counterparts, accordingly improving the response to minute forces.

This protocol describes the design and manufacture of a water bridge and its activation as a water fiber. The experiment demonstrates that capillary resonances of the water fiber modulate its optical transmission.

In this report, an optical fiber of which the core is made solely of water, while the cladding is air, is designed and manufactured. In contrast with ...

Hybrid Printing for the Fabrication of Smart Sensors

A method to combine additively manufactured substrates or foils and multilayer inkjet printing for the fabrication of sensor devices is presented. First, three substrates (acrylate, ceramics, and copper) are prepared. To determine the resulting material properties of these substrates, profilometer, contact angle, scanning electron microscope (SEM), and focused ion beam (FIB) measurements are done. The achievable printing resolution and suitable drop volume for each substrate are, then, found through the drop size tests. Then, layers of insulating and conductive ink are inkjet printed alternately to fabricate the target sensor structures. After each printing step, the respective layers are individually treated by photonic curing. The parameters used for the curing of each layer are adapted depending on the printed ink, as well as on the surface properties of the respective substrate. To confirm the resulting conductivity and to determine the quality of the printed surface, four-point probe and profilometer measurements are done. Finally, a measurement set-up and results achieved by such an all-printed sensor system are shown to demonstrate the achievable quality.

Here we present a protocol for the fabrication of inkjet-printed multilayer sensor structures on additively manufactured substrates and foil.

A method to combine additively manufactured substrates or foils and multilayer inkjet printing for the fabrication of sensor devices is presented. First, ...