Low-Temperature Raman Imaging of Component Distribution in Micron-Size Droplets

Author(s):  
Qishen Huang ◽  
Peter J. Vikesland
Nanoscale ◽  
2017 ◽  
Vol 9 (46) ◽  
pp. 18202-18207 ◽  
Author(s):  
A. Kostopoulou ◽  
M. Sygletou ◽  
K. Brintakis ◽  
A. Lappas ◽  
E. Stratakis

Ultra-thin and highly uniform CsPbBr3 nanowires over micron-size lengths and widths down to the quantum confinement regime have been fabricated via a facile, low-temperature precipitation-based method. This synthesis approach is the first of its kind that is carried out on the work-bench. The nanowires’ photoluminescence is shown to improve over time.


1983 ◽  
Vol 29 ◽  
Author(s):  
V. Daneu ◽  
J. Peers ◽  
A. Sanchez

ABSTRACTWet and dry laser-etching experiments have been performed on polished CdS crystals, using a CW Ar laser, with the goal of writing patterns with μm linewidth. A nitric acid solution was found to exhibit no appreciable dark etching and high photoetching rate; surface roughening due to scattered light was its limitation. A dry, low-temperature (< 200°C) laser-etching process was also studied, and used to produce satisfactory line patterns with 1- to 5-μm linewidths and a 3:1 depth ratio.


2015 ◽  
Vol 2015 (1) ◽  
pp. 000073-000078 ◽  
Author(s):  
Toshinori Ogashiwa ◽  
Kentaro Totsu ◽  
Mitsutomo Nishizawa ◽  
Hiroyuki Ishida ◽  
Yuya Sasaki ◽  
...  

Au/Au hermetic sealing was successfully done using a rim structure covered with sub-micron-size Au particles by low-temperature thermo-compression bonding. The easy deformability of sintered Au particles is advantageous in terms of the compliance with surface irregularity as well as the insensitivity of surface flatness. From the deflection of Si diaphragms over the sealed cavity, an inside pressure of 100 Pa and the maximum leak rate in a range of 10−14 Pa·m3/s (He) were estimated, which is sufficient for many MEMS applications.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Gui-sheng Gan ◽  
Liujie Jiang ◽  
Shiqi Chen ◽  
Yongqiang Deng ◽  
Donghua Yang ◽  
...  

Purpose Low-Ag SAC solder will lead to a series of problems, such as increased the melting range and declined the solderability and so on. These research studies do not have too much impact on the improvement of solders’ performance but were difficult to achieve satisfactory results. It is urgent to develop new soldering technology to avoid the bottleneck of lead-free solder. low-temperature-stirring soldering and ultrasonic-assisted soldering was developed in the authors’ early work, but slag inclusion and pore would gather and grow up to lead decreasing of the shear strength. In this paper, Cu/SAC0307 +Zn power/Cu joints with ultrasonic-assisted at low-temperature was successfully achieved. Design/methodology/approach 45um Zn-powder and SAC0307 No.4 solder powder were mixed to fill the Cu-Cu joint, and the content of Zn-powder were 0 and 5%, 7.5% and 10%, 12.5% and 15% respectively. During the soldering process under ambient atmosphere %252C the heating platform provided a constant 220%253 F and the ultrasonic vibrator applied a constant pressure of 4 MPa to the copper substrate. The soldering process was completed after holding 70 s at 300 W. Findings The Zn particles made the IMC at the joint interface and in the soldering seam from scallop-type Cu6Sn5 to flat-type Cu5Zn8. The shear strength of joints without Zn was only 12.43 MPa, the shear strength of joints with 10% Zn reached a peak of 34.25 MPa, and the shear strength of joints containing 10% Zn was 63.71% higher than that of joints without zinc particles, and then the shear strength decreased. In addition, with the increase of zinc content, the fracture mode of the joint changed from the brittle fracture of the original layered tears to the mixed tough and brittle fracture. Originality/value A new method that Zn micron-size powders and SAC0307 micron-size powders was mixed to fill the joint, and successfully achieved micro-joining of Cu/Cu under ultrasonic-assisted without flux at low-temperature.


2011 ◽  
Vol 88 (8) ◽  
pp. 2275-2277 ◽  
Author(s):  
S. Ishizuka ◽  
N. Akiyama ◽  
T. Ogashiwa ◽  
T. Nishimori ◽  
H. Ishida ◽  
...  

Author(s):  
P.P.K. Smith

Grains of pigeonite, a calcium-poor silicate mineral of the pyroxene group, from the Whin Sill dolerite have been ion-thinned and examined by TEM. The pigeonite is strongly zoned chemically from the composition Wo8En64FS28 in the core to Wo13En34FS53 at the rim. Two phase transformations have occurred during the cooling of this pigeonite:- exsolution of augite, a more calcic pyroxene, and inversion of the pigeonite from the high- temperature C face-centred form to the low-temperature primitive form, with the formation of antiphase boundaries (APB's). Different sequences of these exsolution and inversion reactions, together with different nucleation mechanisms of the augite, have created three distinct microstructures depending on the position in the grain.In the core of the grains small platelets of augite about 0.02μm thick have farmed parallel to the (001) plane (Fig. 1). These are thought to have exsolved by homogeneous nucleation. Subsequently the inversion of the pigeonite has led to the creation of APB's.


Author(s):  
S. Edith Taylor ◽  
Patrick Echlin ◽  
May McKoon ◽  
Thomas L. Hayes

Low temperature x-ray microanalysis (LTXM) of solid biological materials has been documented for Lemna minor L. root tips. This discussion will be limited to a demonstration of LTXM for measuring relative elemental distributions of P,S,Cl and K species within whole cells of tobacco leaves.Mature Wisconsin-38 tobacco was grown in the greenhouse at the University of California, Berkeley and picked daily from the mid-stalk position (leaf #9). The tissue was excised from the right of the mid rib and rapidly frozen in liquid nitrogen slush. It was then placed into an Amray biochamber and maintained at 103K. Fracture faces of the tissue were prepared and carbon-coated in the biochamber. The prepared sample was transferred from the biochamber to the Amray 1000A SEM equipped with a cold stage to maintain low temperatures at 103K. Analyses were performed using a tungsten source with accelerating voltages of 17.5 to 20 KV and beam currents from 1-2nA.


Author(s):  
P. Echlin ◽  
M. McKoon ◽  
E.S. Taylor ◽  
C.E. Thomas ◽  
K.L. Maloney ◽  
...  

Although sections of frozen salt solutions have been used as standards for x-ray microanalysis, such solutions are less useful when analysed in the bulk form. They are poor thermal and electrical conductors and severe phase separation occurs during the cooling process. Following a suggestion by Whitecross et al we have made up a series of salt solutions containing a small amount of graphite to improve the sample conductivity. In addition, we have incorporated a polymer to ensure the formation of microcrystalline ice and a consequent homogenity of salt dispersion within the frozen matrix. The mixtures have been used to standardize the analytical procedures applied to frozen hydrated bulk specimens based on the peak/background analytical method and to measure the absolute concentration of elements in developing roots.


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