Glass Bulb Research Articles

Harsh environment resistible and recyclable thermoplastic polyurea adhesive based on stable and density hydrogen bonds

Adhesives are crucial in a variety of applications, including transportation, building, electronics, aerospace and even human organs etc. However, tens of millions of tons of adhesives used world widely couldn’t be recycled due to the chemically crosslinked structure, especially for those used in harsh environments. Here, we synthesized a self-healing thermoplastic polyurea with ultra-high hydrogen bonding by ending capped with UPy and excellent harsh environment resistible and recyclable capability by utilizing PDMS as the only soft segment. For a property balanced sample, PDMS-12, it exhibited high degree of hydrogen bonding association of 92.5 % at 30 ℃ and gradually decayed after 80 ℃, after which its adhesion was stimulated as revealed by rheological test. If the pure PDMS-12 was immersed in water, pH = 1 acid, pH = 14 alkali, oil, and simulated seawater for up to 30 days, its initial adhesion strength declined between 48 % and 70 %. When it was already glued between different matrixes, the lap shear strength dropped by 0.7 % to 80 %, depending on the types of matrixes and liquid environments. Nonetheless, the remaining adhesion strength was always strong enough to lift weights of ∼ 5.0 kg and can be reused after cleaning. What’s more, a 0.5 mm glue coating could successfully protect a glass bulb from an impact of 0.5 kg weight at approximately −196 ℃, proving its potential application in fragile fields like electrical industry.

A Simple High-Flux Switchable VUV Lamp Based on an Electrodeless Fluorescent Lamp for SPI/PAI Mass Spectrometry.

Single-photon ionization (SPI) is a unique soft ionization technique for organic analysis. A convenient high-flux vacuum ultraviolet (VUV) light source is a key precondition for wide application of SPI techniques. In this study, we present a novel VUV lamp by simply modifying an ordinary electrodeless fluorescent lamp. By replacing the glass bulb with a stainless steel bulb and introducing 5% Kr/He (v/v) as the excitation gas, an excellent VUV photon flux over 4.0 × 1014 photons s-1 was obtained. Due to its rapid glow characteristics, the VUV lamp can be switched on and off instantly as required by detection, ensuring the stability and service life of the lamp. To demonstrate the performance of the new lamp, the switchable VUV lamp was coupled with an SPI-mass spectrometer, which could be changed to photoinduced associative ionization (PAI) mode by doping gaseous CH2Cl2 to initiate an associative ionization reaction. Two types of volatile organic compounds sensitive to SPI and PAI, typically benzene series and oxygenated organics, respectively, were selected as samples. The instrument exhibited a high detection sensitivity for the tested compounds. With a measurement time of 11 s, the 3σ limits of detection ranged from 0.33 to 0.75 pptv in SPI mode and from 0.03 to 0.12 pptv in PAI mode. This study provides an extremely simple method to assemble a VUV lamp with many merits, e.g., portability, robustness, durability, low cost, and high flux. The VUV lamp may contribute to the development of SPI-related highly sensitive detection technologies.

Characterization of the LED filament lamp for luminous intensity calibration

Light-emitting diode (LED) is now the main type of light source in global lighting marketing. However, traditional photometry with the incandescent standard lamp is not sufficient to implement high-level LED photometric measurement, since a considerable spectral mismatch error may exist if the photometer has a large general V(λ) mismatch index . The LED standard lamp is proposed to be the complementary transfer standard for photometry to reduce this measurement uncertainty. National Institute of Metrology, China (NIM) has previously reported a type of LED filament lamp for total luminous flux. In this article, NIM demonstrates another type of LED filament lamp for luminous intensity calibration. The LED filaments are sealed in a T90 cylinder glass bulb as emitters, and have a spectrum similar to the reference white LED spectrum considered in Commission on Illumination technical committee 2–90. The LED lamp uses the E27 screw base as the connector, and is compatible with the traditional alignment approaches. The warm-up time is less than 12 min. The output change of a group of 12 lamps, over nearly two years of storage and 1 h operation every day during the whole long-term test, is found to be ±0.2% or less for most of the lamps. The ageing effect of one lamp over a continuous 6500 h of burning is estimated to be −0.014% per 100 h, and it is significantly lower than 1% per 100 h, the typical drift rate of the traditional incandescent luminous intensity lamp. In the aspect of the coincidence with inverse square law, the LED lamp has a similar performance to the WI41/G lamp, the traditional luminous intensity lamp.

Design and Construction of Ultraviolet and Incoming Solar Irradiance Sensing Device

In-situ measurements of ultraviolet (UV) and solar irradiance is very sparse in Nigeria because of cost; it is estimated using meteorological parameters. In this work, a low-cost UV and pyranometer device, using locally sourced materials, was developed. The instrument consists of a UV sensor (ML8511), a photodiode (BPW34) housed in a carefully sealed vacuumed glass bulb, the UV and solar irradiance sensor amplifiers, a 16-bit analog-to-digital converter (ADS1115), Arduino mega 2560, liquid crystal display (LCD) and microSD card for data logging. The designed amplifier has an offset voltage of 0.8676 mV. The sensitivity of the irradiance device is 86.819 Wm-2/mV with a correcting factor of 27.77 Wm-2 and a maximum range of 1200 Wm-2. The instrument validation error is 9.67% and a correlation coefficient of 0.89 when compared with a standard SRS100 pyranometer. The UV sensor showed a close response with a correlation of 0.99 in comparison with a standard Skye instrument. From 08:00 to 16:00 local time (LT), there is a very close agreement between the standard device and the developed counterpart, with marginal differences of about 9.6% observed at the two extremes.

Microemitter-Based IR Spectroscopy and Imaging with Multilayer Graphene Thermal Emission.

IR analyses such as Fourier transform infrared spectroscopy (FTIR) are widely used in many fields; however, the performance of FTIR is limited by the slow speed (∼10 Hz), large footprint (∼ millimeter), and glass bulb structure of IR light sources. Herein, we present IR spectroscopy and imaging based on multilayer-graphene microemitters, which have distinct features: a planar structure, bright intensity, a small footprint (sub-μm2), and high modulation speed of >50 kHz. We developed an IR analysis system based on the multilayer-graphene microemitter and performed IR absorption spectroscopy. We show two-dimensional IR chemical imaging that visualizes the distribution of the chemical information. In addition, we present high-spatial-resolution IR imaging with a spatial resolution of ∼1 μm, far higher than the diffraction limit. The graphene-based IR spectroscopy and imaging can open new routes for IR applications in chemistry, material science, medicine, biology, electronics, and physics.

A Novel Method for Rubidium Bulb Bonding and Key Characterization for Future Space Clocks.

RF-discharge lamp is a key component in space- and ground-based compact and portable atomic clocks, such as rubidium atomic frequency standards (RAFSs). Precise thermal, structural design, and control of a rubidium (Rb) bulb is of crucial importance for long-term reliable operation of the onboard clocks. An important aspect is the potting material that is used to mount the Rb bulb. Potting material directly determines the thermal contact between liquid Rb pool inside glass bulb enclosure and the heating element, which is the only path to control the Rb bulb's temperature. Failure or degradation of thermal contact of the Rb bulb with its metallic base will lead to Rb clock degradation or failure. Considering this, we have successfully designed, simulated, implemented, characterized, and tested the use of indium metal as a replacement to epoxy for the Rb bulb bonding that can be implemented in future space Rb atomic clocks. Its thermal advantage over other routine space-qualified epoxies and flexibility for multiple bonding and unbonding mechanisms make it ideal for such applications. The usefulness of key properties of indium for various other space and ground applications is discussed.

Laser operator duty cycle effect on temperature and thermal dose: in-vitro study.

High-power laser lithotripsy can elevate temperature within the urinary collecting system and increase risk of thermal injury. Temperature elevation is dependent on power settings and operator duty cycle (ODC)-the percentage of time the laser pedal is depressed. The objective of this study was to quantify temperature and thermal dose resulting from laser activation at different ODC in an in-vitro model. Holmium laser energy (1800J) was delivered at 30W (0.5J × 60Hz) to a fluid filled glass bulb. Room temperature irrigation was applied at 8ml/min. ODC was evaluated in 10% increments from 50-100%. Bulb fluid temperature was recorded and thermal dose calculated. Time to reach threshold of thermal injury and maximal allowable energy were also determined at each ODC. Upon laser activation, there was an immediate rise in fluid temperature with a "saw-tooth" oscillation superimposed on the curves for 50-90% ODC corresponding to periodic activation of the laser. Higher ODC resulted in greater maximum temperature and thermal dose, with ODC ≥ 70% exceeding threshold. Use of 50% compared to 60% ODC resulted in a tenfold increase in time required to reach threshold of thermal injury and an eightfold increase in maximal allowable energy. Laser activation at higher ODC produced greater fluid temperature and thermal dose. Time to threshold of thermal injury and maximal allowable energy were dramatically higher for 50% compared to 60% ODC at high-power settings. Proper management of laser ODC can enhance patient safety and optimize stone treatment.

Comparison of forces for the Crookes and Hettner radiometers

The Crookes radiometer (also known as a light mill) is a fascinating sunlight-powered device, in which a set of vanes is placed inside a glass bulb within which a partial vacuum has been pulled. The vanes then rotate when sunlight shines on the bulb. The reason for the turning of the vanes was subject to intense debate and many students still have an incorrect understanding of the device. We analyse the forces involved in a much less well-known radiometer (called the Hettner radiometer) and show that this can help us to understand the forces involved in the Crookes radiometer in a more unified way.

Pelvicaliceal Volume and Fluid Temperature Elevation During Laser Lithotripsy.

Background: While high-power laser systems facilitate successful ureteroscopic treatment of larger and more complex stones, they can substantially elevate collecting system fluid temperatures with potential thermal injury of adjacent tissue. The volume of fluid in which laser activation occurs is an important factor when assessing temperature elevation. The aim of this study was to measure fluid temperature elevation and calculate thermal dose from laser activation in fluid-filled glass bulbs simulating varying calix/pelvis volumes. Materials and Methods: Glass bulbs of volumes 0.5, 2.8, 4.0, 7.0, 21.0, and 60.8 mL were submerged in a 16-L tank of 37°C deionized (DI) water. A 230-μm laser fiber extending 5 mm from the tip of a ureteroscope was positioned in the center of each glass bulb. Irrigation with 0, 8, 15, and 40 mL/min of room temperature DI water was applied. Once steady-state temperature was achieved, a Ho:YAG laser was activated for 60 seconds at 40 W (0.5 J × 80 Hz, SP). Temperature was measured from a thermocouple affixed to the external tip of the ureteroscope. Thermal dose was calculated using the Dewey and Sapareto t43 methodology. Results: The extent of temperature elevation and thermal dose from laser activation were inversely related to the volume of fluid in each model and the irrigation rate. The time to threshold of thermal injury was only 3 seconds for the smallest model (0.5 mL) without irrigation but was not reached in the largest model (60.8 mL) regardless of irrigation rate. Irrigation delivered at 40 mL/min maintained safe temperatures below the threshold of tissue injury in all models with 1 minute of continuous laser activation. Conclusions: The volume of fluid in which laser activation occurs is an important factor in determining the extent of temperature elevation. Smaller volumes receive greater thermal dose and reach threshold of tissue injury more rapidly than larger volumes.

Design and implementation of combined liquid pump and active–passive mixer for a drug delivery system utilizing two 1-DOF piezoelectric actuated cantilever beams

In a biomedical drug delivery system, liquid medication is provided to the patient through a saline solution, administered in tiny drops. The spread of the medicine in the solution is an essential aspect for the solution to become homogeneous. The present study introduces a combined pump and active–passive mixer arrangement consisting of dual piezoelectrically actuated 1-degree of freedom (DOF) Aluminium cantilever beams. The free end of each beam is attached to a borosilicate glass tube set-up that works as both pump and a mixer. The setup consists of two vertical tubes, connecting channels, a glass bulb, and a coiled tube. When the piezoelectric actuated cantilever beam is excited by an excitation voltage, it deflects and vibrates along with the glass tube arrangement resulting in the vertical tubes pumping liquid from the two separate glass containers due to the mechanical vibratory movement. The connecting channels pass the pumped fluid into the vibrating glass bulb and the coiled tube where these two liquids mix. We tested the mixing executions of four different geometries, G-1 – G-4, based on changed δ (coil curvature ratio), p (pitch), and n (number of windings). Initial pumping was started at 90 VP-P input voltage for all geometries, and the observed flow rate and velocity were 2.91 ml min−1 and 0.9160 mm min−1 for G-1 geometry. A UV–visible spectrophotometer was used to evaluate the mixing execution by measuring the solution's absorbance values before and after mixing.

MP10-18 EFFECT OF CHILLED IRRIGATION ON CALYCEAL FLUID TEMPERATURE AND TIME TO THERMAL INJURY THRESHOLD DURING LASER LITHOTRIPSY: IN VITRO MODEL

You have accessJournal of UrologySurgical Technology & Simulation: Instrumentation & Technology I (MP10)1 Sep 2021MP10-18 EFFECT OF CHILLED IRRIGATION ON CALYCEAL FLUID TEMPERATURE AND TIME TO THERMAL INJURY THRESHOLD DURING LASER LITHOTRIPSY: IN VITRO MODEL Julie J. Dau, Timothy L. Hall, Adam D. Maxwell, Khurshid R. Ghani, and William W. Roberts Julie J. DauJulie J. Dau More articles by this author , Timothy L. HallTimothy L. Hall More articles by this author , Adam D. MaxwellAdam D. Maxwell More articles by this author , Khurshid R. GhaniKhurshid R. Ghani More articles by this author , and William W. RobertsWilliam W. Roberts More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000001983.18AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: High-power lasers (100-120W) have widely expanded the available settings for laser lithotripsy and facilitated tailoring of treatment for individual cases. Previous in vitro and in vivo studies have demonstrated that a toxic thermal dose to tissue can result from treatment within a renal calyx. The objective of this in vitro study was to compare thermal dose and time to tissue injury threshold when using chilled irrigation and room temperature irrigation. METHODS: A glass tube attached to a 21 mm diameter bulb simulating a renal calyx was placed in a 37°C water bath. A 242 µm laser fiber was passed through a ureteroscope with its tip in the center of the glass bulb. A wire thermocouple was placed at the level of the ureteroscope tip to measure calyceal fluid temperature. Room temperature (RT) at 19°C or chilled (CH) at 1°C irrigation was delivered at 0, 8, 12, 15, or 40 ml/min. The laser was activated at 0.5J x 80Hz (40W) for 60 seconds. Thermal dose was calculated using the Sapareto and Dewey t43 methodology with thermal dose = 120 equivalent minutes considered the threshold for thermal tissue injury. RESULTS: At each irrigation rate, CH irrigation produced a lower starting temperature, a lower plateau temperature, and less thermal dose compared to RT irrigation. The threshold of thermal injury was reached after 13 seconds of laser activation without irrigation. With 12 ml/min irrigation, the threshold was reached in 46 seconds with RT irrigation but was not reached with CH irrigation. CONCLUSIONS: As higher power laser lithotripsy techniques become further refined, methods to mitigate and control thermal dose are necessary to enhance efficiency. CH irrigation slows temperature rise, decreases plateau temperature, and lowers thermal dose during high power laser lithotripsy. Source of Funding: Funding for this research was provided through a research grant from Boston Scientific © 2021 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 206Issue Supplement 3September 2021Page: e175-e175 Advertisement Copyright & Permissions© 2021 by American Urological Association Education and Research, Inc.MetricsAuthor Information Julie J. Dau More articles by this author Timothy L. Hall More articles by this author Adam D. Maxwell More articles by this author Khurshid R. Ghani More articles by this author William W. Roberts More articles by this author Expand All Advertisement Loading ...

PD41-06 EFFECT OF PELVICALYCEAL FLUID VOLUME ON TEMPERATURE ELEVATION AND THERMAL DOSE DURING LASER LITHOTRIPSY

You have accessJournal of UrologySurgical Technology & Simulation: Instrumentation & Technology II (PD41)1 Sep 2021PD41-06 EFFECT OF PELVICALYCEAL FLUID VOLUME ON TEMPERATURE ELEVATION AND THERMAL DOSE DURING LASER LITHOTRIPSY Nikta R. Khajeh, Timothy L. Hall, Khurshid R. Ghani, and William W. Roberts Nikta R. KhajehNikta R. Khajeh More articles by this author , Timothy L. HallTimothy L. Hall More articles by this author , Khurshid R. GhaniKhurshid R. Ghani More articles by this author , and William W. RobertsWilliam W. Roberts More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002051.06AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: While high-power holmium lasers facilitate successful ureteroscopic treatment of larger and more complex stones, they can also substantially elevate fluid temperatures in the ureter and collecting system potentially causing thermal injury of the adjacent tissue. Fluid volume is an important factor when assessing temperature elevation. The aim of this study was to investigate temperature elevation and thermal dose from laser lithotripsy in model calyces/pelvises spanning a clinically relevant range of fluid volumes. METHODS: Glass bulbs of volumes 0.5, 2.8, 4.0, 7.0, 21.0, and 60.8 mL served as calyx/pelvis models. A single bulb was submerged in a tank of 37˚C deionized (DI) water to simulate core body temperature. A 230 µm core laser fiber extending 5 mm from the tip of a LithoVue ureteroscope was positioned in the center of the model. Irrigation settings of 0, 8, 15, and 40 ml/min with room temperature DI water were used while a P120 Ho:YAG laser was activated for 60 seconds at 40W (0.5 J x 80 Hz, SP). Temperature was measured every second by a thermocouple affixed 5 mm from the tip of the ureteroscope. 5 trials were run under each parameter. Thermal dose was calculated from the temperature curves using the Dewey and Sapareto t43 methodology with t43=120 equivalent minutes accepted as the threshold for thermal injury. RESULTS: The rate of temperature elevation and thermal dose from laser activation were inversely proportional to the volume of fluid in each model and the irrigation rate. The time to threshold for thermal injury was only 3 seconds for the smallest model (0.5 ml) without irrigation, while it was never reached in the largest model (60.8 mL), regardless of irrigation rate (table). 40 ml/min irrigation maintained safe temperatures below the threshold for injury in all models (figure). CONCLUSIONS: Clinicians should be mindful when using high power laser settings in confined calyxes, or tight spaces as heating of small volume fluid to dangerous levels can occur quickly. Source of Funding: Research grant from Boston Scientific © 2021 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 206Issue Supplement 3September 2021Page: e682-e683 Advertisement Copyright & Permissions© 2021 by American Urological Association Education and Research, Inc.MetricsAuthor Information Nikta R. Khajeh More articles by this author Timothy L. Hall More articles by this author Khurshid R. Ghani More articles by this author William W. Roberts More articles by this author Expand All Advertisement Loading ...

Sand Clock and The Concept of Time in Einstein’s Theory of Relativity

The sand clock is a device used to measure time, consisting of two conical glass bulbs, which are connected vertically by a small opening neck. The top contains grains of fine dry sand. The upper part symbolizes the future, sand passes through the neck (which indicates present) to the lower part which turned past. In 1907, German scientist Hermann Minkowski (1864-1909) interpreted the concept of the four-dimensional space-time of Einstein's theory in a two-dimensional cone diagram, in which the upper cone symbolizes the future, the neck the present and the lower part the past. The researcher has noticed a great likeness, to the point of congruence between the shape and function of both, the sand clock and the diagram. This resemblance aroused speculations that Hermann Minkowski had been inspired by the sand hour in drawing his diagram. It cannot be attributed to a merely chance.

Investigation of the Conditions for the Use of Material with the Shape Memory Effect in the Sprinklers

The expediency of using nitinol, which is a material with the shape memory effect (SME), as a sensitive element (SE) of a sprinkler has been substantiated. The influence of various parameters on the SE dimensions is analyzed and it is shown that the response time of an element made of a material with the shape memory effect depends on the dimensions of the fixing device (FD) (the diameter of the glass bulb and its thickness). Calculations have shown that the use of the material minimizes the response time of the sprinkler. It is shown that the response time depends on the voltage (or current) in the electrical network, on the size of the fixing device, the cross-sectional radius of the actuator and the critical temperature at which the actuator is triggered.

Automatic Version of Ostwald Viscometer for Conductive Liquids

In this automatic version of Ostwald electro viscometer some major modifications have been introduced. Namely, we have inserted the Pt wire level sensors within upper glass bulb, modified electrical circuitry with logic XOR gate, added digital stopwatch to find the time of fluidity of some liquids very accurately. In modified version of viscometer there is no requirement of any type of glass window of thermostat to check the liquid levels during fluidity at high temperature. The viscosity measurements were done through electro viscometer with an accuracy of ±0.001 mPa s.

Burnback: the role of pulse duration and energy on fiber-tip degradation during high-power laser lithotripsy.

High-power holmium lasers have become popular for ureteroscopic laser lithotripsy and dusting. Our aim was to investigate the effect of pulse duration and pulse energy on fiber-tip degradation when using high-power settings for popcorn lithotripsy. BegoStones were fragmented in a glass bulb to simulate renal calyx, using a 120W Ho:YAG laser. A 242μm fiber was placed via the ureteroscope 2mm distance from stones (popcorn model). To assess the effect of pulse duration on fiber-tip degradation, long pulse (LP) and short pulse (SP) settings were compared at settings of 1.0Jx20Hz (20W), 0.5Jx70Hz (35W), and 1.0Jx40Hz (40W). To assess the effect of pulse energy on tip degradation, 40W SP settings (0.5Jx80Hz, 0.8Jx50Hz, and 1.0Jx40Hz) were tested. Pulse duration was measured using a photodetector and peak power was then calculated using the pulse duration and pulse energy. Experiments were conducted for 4min. Fiber-tip length was measured before and after using a digital caliper. Fiber-tip degradation was least when using LP for all settings tested (p < 0.01). For 40W settings, tip degradation was significantly lower when using a pulse energy of 0.5J compared to 0.8J or 1.0J (p < 0.004). LP mode results in less fiber burnback for all power settings tested. Total power is more important than frequency in the development of burnback. However, high-power 40W settings can be utilized with less burnback if lower pulse energies are used. Understanding these parameters can improve the longevity of the laser fiber and improve procedural efficiency.

Patterns of Laser Activation During Ureteroscopic Lithotripsy: Effects on Caliceal Fluid Temperature and Thermal Dose.

Introduction: Characterizing patterns of laser activation is important for assessing thermal dose during laser lithotripsy. The objective of this study was twofold: first, to quantify the range of operator duty cycle (ODC) and pedal activation time during clinical laser lithotripsy procedures, and second, to determine thermal dose in an in vitro caliceal model when 1200 J of energy was applied with different patterns of 50% ODC for 60 seconds. Methods: Data from laser logs of ureteroscopy cases performed over a 3-month period were used to calculate ODC (lasing time/lithotripsy time). Temporal and rolling 1-minute average power tracings were generated for each case. In vitro experiments were conducted using a 21 mm diameter glass bulb in a 37°C water bath, simulating a renal calix. A LithoVue ureteroscope with attached thermocouple was inserted and 8 mL/min irrigation was delivered with a 242 μm laser fiber within the working channel. In total, 1200 J of laser energy was applied in five different patterns at 20 W average power for 60 seconds. Thermal dose was calculated using the Sapareto and Dewey t43 method. Results: A total of 63 clinical cases were included in the analysis. Mean ODC was 32% overall and 63% during the 1-minute of greatest energy delivery. Mean time of pedal activation was 3.6 seconds. In vitro studies revealed longer pedal activation times produced higher peak temperature and thermal dose. Thermal injury threshold was reached in 9 seconds when 40 W was applied at 50% ODC with laser activation patterns of 30 seconds on/off and 15 seconds on/off. Conclusion: ODC was quantified from clinical laser lithotripsy cases: 32% overall and 63% during 1-minute of peak power. Time of pedal activation is an important factor contributing to fluid heating and thermal dose. Awareness of these concepts is necessary to reduce risk of thermal injury during laser lithotripsy procedures.

Experimental Evaluation of Liquid Mixing Using Piezo Actuated Pump System

In present work, two piezo actuated cantilever beams are connected to a glass tube setup. The glass tube arrangement consists of the vertical tubes inserted in the liquid solutions, connector tubes, a glass bulb, and a helical tube, and it acts as a pump and mixer. When the piezo actuators are energized by AC voltage, vertical tubes start pumping the solution. At whatever point the two different solutions are in contact with each other in vibrating glass bulb and helical tube, mixing occurs. The proposed technique is a combination of active and passive mixers in which the liquid pumping action is utilized for fluid mixing. The diverse flowrates acquired at 65, 75, and 80 Vp-p are 0.038, 0.05012, and 0.06976 mL/s. UV-vis spectrophotometer tests mixed solutions for mixing performance. The important findings are, mixing performance depends upon two parameters, viz. solution concentration and flowrate.

Quantitative comparisons of moth-trap catches

A simple method was used to compare the catches of seven different pairs of light-emitting moth-traps. Numbers of macro-moth individuals and species caught nightly by each member of a pair were recorded in comparisons that lasted between ten and 79 nights. A Robinson trap made significantly larger catches than a Skinner trap with an identical bulb, and a Robinson trap at ground level made significantly larger catches than an identical trap at a height of 90 cm. A 125 W MV bulb made significantly larger catches than an equivalent Wood's glass bulb or a multiple LED dome. No significant differences were found between a Robinson trap with a 125 W MV bulb and one with an 80 W MV bulb, or between two commercial brands of 125 W MV bulbs, or between two identical 125 W MV bulbs. This last comparison showed significant differences between the two sites used for these trials, apparently caused by a large flowering Buddleia at the more productive site. The findings suggest that catches may be maximised by using Robinson moth traps with 125 W MV bulbs, rather than the other traps or light sources tested here, and by placing them on the ground close to flowering Buddleia or other nectar-rich shrubs.

Notes on a brilliant failure

The article “Ernest Lawrence’s brilliant failure” by Joshua Roebke (Physics Today, March 2019, page 32) gives a historical account of early work by the Nobel recipient and his associates at the University of California, Berkeley, to invent color TV. An alumnus of both Berkeley and the TV industry (1964–2006), I was surprised and pleased to learn of that work. I had not realized that Sony’s Trinitron technology traces its origin back to Berkeley and Lawrence.However, I was shocked by several inaccuracies. The article is misleading regarding the basic principles of the color CRT (cathode-ray tube), and it does not present an accurate account of the pre-flat-panel display industry.The article claims that Sony’s Trinitron CRT was the best-selling television in the world and was the color TV most Americans grew up with. That is incorrect. From the beginning of color broadcasting in 1954 to the mid 2000s, RCA’s color CRT was the dominant one.Sony’s Trinitron was commercially introduced in 1968, 14 years after the start of the color TV industry. Virtually no other company manufactured color TVs with Trinitron displays. During the pre-flat-panel color TV era, Sony sold fewer than 300 million color TVs with Trinitrons; the rest of the industry globally sold well over 10 times as many sets with the RCA color CRT. Although RCA only manufactured in the US, it licensed its technology abroad; in several cases RCA provided direct engineering support for licensees’ manufacturing plants. All color TV manufacturers worldwide, including Sony, were RCA licensees.11. J. A. Castellano, SID Symp. Dig. Tech. Pap. 30, 356 (1999); https://doi.org/10.1889/1.1834031A. Monchamp et al., Cathode Ray Tube Manufacturing and Recycling: Analysis of Industry Survey, Electronic Industries Alliance (2001).The fundamental physical principles of the Sony and RCA color CRTs were identical. Both used three intensity-modulated electron guns to carry the three-color image information. Contrary to the article, the Trinitron did not use a single source for the three beams.The beams were scanned by a common magnetic deflection system. In both the Sony and the RCA devices, a metal mask with small openings was placed at a precise distance between the screen and the electron guns. The beams emerged from each opening at slightly different angles and landed on the screen at three slightly displaced, nonoverlapping locations, where a trio of red, green, and blue light-emitting phosphor elements were positioned. To prevent the excitation of adjacent phosphor elements, the mask transmission is necessarily restricted to less than ⅓.The Sony and RCA approaches used differently shaped masks. Sony’s was made of tensioned metal strips forming a vertical standing cylinder. RCA’s mask was best described as spherical. Thus the Sony guns were arranged horizontally, whereas the RCA ones had a triangle configuration. Both systems worked well. The price of color TVs was determined by the cost of the CRTs, which was mainly driven by the cost of their glass bulbs. Because the RCA approach was somewhat less expensive, it dominated the consumer market.ReferenceSection:ChooseTop of pageReference <<CITING ARTICLES1. J. A. Castellano, SID Symp. Dig. Tech. Pap. 30, 356 (1999); https://doi.org/10.1889/1.1834031, Google ScholarCrossrefA. Monchamp et al., Cathode Ray Tube Manufacturing and Recycling: Analysis of Industry Survey, Electronic Industries Alliance (2001). , Google Scholar© 2019 American Institute of Physics.