Diamond Anvil cell

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Diamond anvil cell partitioning experiments for accretion and core formation: testing the limitations of electron microprobe analysis

Diamond anvil cell partitioning experiments for accretion and core formation: testing the limitations of electron microprobe analysis

Experimental studies typically examine partitioning of various elements between liquid metal and silicate melt. These are performed at high temperature (T) (>1500 K) over a range of experimentally-accessible pressures (P) in piston-cylinder or multi-anvil apparatus, and measured by electron probe microanalyser (EPMA) and/or laser-ablation inductively-coupled plasma mass spectrometry (LA-ICP-MS). Both siderophile element (Ni, Co and others: e.g. Li and Agee, 1996; Righter et al., 1997; Geßmann and Rubie, 1998) and light element (e.g. Si, Geßmann et al., 2001; O, Tsuno et al., 2013; C, Dasgupta et al., 2013; S, Kilburn and Wood, 1997) partitioning have traditionally been examined in this way. Following the initial study of Bouhifd and Jephcoat (2003), the use of Diamond Anvil Cell (DAC) experiments to access higher PT conditions more relevant for core formation in large bodies has become increasingly common for examining both siderophile and lithophile element partitioning. It is noted from such experiments that pressure trends obtained from the larger volume, lower pressure experiments do not always extrapolate to those identified at much higher pressures in DAC experiments (e.g. Suer et al., 2017). At the very high PT conditions achievable in a DAC, light elements in particular may become much more compatible in liquid iron (e.g. Frost et al., 2010), suggesting that some elements that are traditionally thought of as entirely incompatible in metal may be present in Earth’s core in non-negligible concentrations (e.g. Badro et al., 2016; Blanchard et al., 2017).
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Hydrogenation of monolayer graphene in the diamond anvil cell and supercritical phenomena in methane

Hydrogenation of monolayer graphene in the diamond anvil cell and supercritical phenomena in methane

Figure 4.4 shows the method in which methane is loaded into a diamond anvil cell. In the same way as with hydrogen loadings (§ 4.1.1), cells are calibrated such that there is a known amount of turns required on the screws for the cell to close completely, and the cell is placed inside a container. The container for methane loadings is a sealable steel vessel with thick Perspex viewing window at the top, through which two copper pipes allow for the flow of methane through the vessel. The vessel is purged thoroughly with methane (CP grade, 99.5%, BOC) and submerged to its brim in liquid nitrogen. As the vessel cools below the boiling curve, methane starts to condense and liquid methane collects. When enough liquid methane has collected, the vessel is opened and the DAC closed before lifting out of the vessel.
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Electric discharge machine for preparation of diamond anvil cell sample chambers

Electric discharge machine for preparation of diamond anvil cell sample chambers

Since installing the automatic stage movement, the smallest sample chamber we have attempted to drill is 100 µm diameter, for an experiment using a DAC equipped with 250 µm diameter cule[r]

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Pore shape modification of a microporous metal–organic framework using high pressure : accessing a new phase with oversized guest molecules

Pore shape modification of a microporous metal–organic framework using high pressure : accessing a new phase with oversized guest molecules

idazolate framework) a similar structural response has been ob- served for different adsorbates under very different conditions. The structure is observed by X-ray diffraction to undergo a tran- sition involving a rotation of the MeIm linkers which increases the porosity of the framework, allowing more guest molecules to enter the pores. This occurs at 0.02 bar in nitrogen gas at 77 K and also at 1,5 GPa in liquid methanol at 298 K. The latter was observed for a single crystal of ZIF-8 loaded into a diamond anvil cell (DAC) and surrounded with methanol as a pressure- transmitting liquid (to ensure pressure is applied hydrostatically to the sample) 14 17-19 The high-pressure structure was used to
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Strength Study of Zircon Under High Pressure

Strength Study of Zircon Under High Pressure

Two main types of apparatus are commonly used in high pressure static experiments: Large Volume Press (LVP) and Diamond-Anvil Cell (DAC). The main idea of the LVP experiment is to squeeze the sample between tungsten carbide anvils. However, the larger sample size has the limitation related to achievement of pressure, as it is hard to achieve pressure higher than 35-37 GPa without braking the tungsten carbide anvils (Xu et al., 2002). The “comfortable” pressure range for the most types of the LVP is below 23 GPa. With a diamond- anvil cell one can obtain pressure up to 300 GPa by using diamonds of gem quality. Certain other flawless gem stones were tested as possible diamond substitute, such as sapphire and cubic zirconia, but the maximum possible pressure reached by using those materials did not exceed 30 GPa (25.8 and 16.7 respectively) (Xu et al., 1996, 2002). Another synthetic analogue of diamond - moissanite was recently used in DAC. Experiments conducted with it were successful and allowed scientists to acquire pressure more than 50 GPa (Xu et al., 2002).
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Optical Properties, Electronic Structures and High Pressure Study of Nanostructured One Dimensional Titanium Dioxide by Synchrotron Radiation and Spectroscopy

Optical Properties, Electronic Structures and High Pressure Study of Nanostructured One Dimensional Titanium Dioxide by Synchrotron Radiation and Spectroscopy

High pressure, diamond anvil cell, synchrotron X-ray diffraction, Raman, X-ray absorption near edge structure, X-ray excited optical luminescence, phase transition, b[r]

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In situ characterization of elusive salt hydrates : the crystal structures of the heptahydrate and octahydrate of sodium sulfate

In situ characterization of elusive salt hydrates : the crystal structures of the heptahydrate and octahydrate of sodium sulfate

for the first time by in situ single crystal X-ray diffraction. The crystal structure shows that each sodium cation is octahedrally coordinated to water molecules, with a slight distortion due to one of the water molecules being disordered. The hydrated sodium cations are hydrogen-bonded to form a three-dimensional bonded network, which is markedly different from the architecture of one-dimensional bonded chains observed in sodium sulfate decahydrate (mirabilite). This major structural difference explains the reconstructive nature of the transformation observed between the heptahydrate and mirabilite. High-pressure crystallization of a 3.41 mol/kg water aqueous solution of sodium sulfate at 1.54 GPa in a diamond-anvil cell resulted in the formation of a previously unknown sodium sulfate hydrate, which we have determined by single crystal X-ray diffraction methods to be an octahydrate, Na 2 SO 4 · 8H 2 O. In this structure the sulfate
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Applications of Nuclear Resonant Scattering to Further Our Understanding of Earth’s Interior

Applications of Nuclear Resonant Scattering to Further Our Understanding of Earth’s Interior

To carry out the X-ray diffraction measurement, the first step is to remotely locate the sample in the X-ray’s focus. This step is usually carried out with a 3-dimensional translation stage system, a zoom camera and a point detector (pin-diode or APD) to measure the X-ray’s intensity. The X-ray is first focused on a thin YAG scintillator plate (∼300 µm thick) so that the camera can capture its fluorescent image. The camera is then zoomed in, focused and centered onto the X-ray’s fluorescent image on the YAG scintillator plate with the translation stage system and fiducialize the image with the position of the X-rays. Then, the YAG scintillator plate is replaced by the sample in the diamond anvil cell, and we focus and center the sample’s image in the camera using the translation stage system while keeping the camera fixed. A diamond correction is then made by moving the sample toward the propagation direction of the X-ray to compensate for the diamond’s index of refraction. The value of the diamond correction varies with the diamond height used in the experiment. In our case, the diamonds are ∼2 mm thick, thus correction is around 1.15 mm. Then, the camera is moved out of the X-ray’s path and the point detector is moved in. Then, we scan the sample horizontally and vertically to fine-tune the sample’s position relative to the center of the X-ray. This fine-tune step is only possible when the sample’s absorption of the incident X-ray is significantly different from the gasket or the pressure medium. In some X-ray diffraction beamlines, the sample position relative to the stage rotation center is also fine-tuned by rotating and scanning the diamond anvil cell horizontally. If the sample’s horizontal center doesn’t change with and without the rotation, the sample is co-axial with the horizontal rotation axis. The rotation is applied when one needs to increase the 2θ range of the X-ray diffraction patterns, or to remove strong diffraction peaks of the diamond single crystal.
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Osteogenic cell differentiation on H-terminated and O-terminated nanocrystalline diamond films

Osteogenic cell differentiation on H-terminated and O-terminated nanocrystalline diamond films

On day 14 postconfluence, the total RNA was extracted from the cell layers by using RNAzol (Molecular Research Center, Cincinnati, OH, USA) according to the manufac- turer’s protocol. Reverse transcription was performed by using oligo-dT primers and the ProtoScript M-MuLV First Strand cDNA Synthesis Kit (New England Biolabs, Ipswich, MA, USA) according to the manufacturer’s protocol. The real-time PCR reactions were performed by using FastStart Universal SYBR Green Master Mix (Hoffman-La Roche Ltd., Basel, Switzerland) on the iQ5 Multicolor Real-Time PCR Detection System (Bio-Rad Laboratories, Inc., Hercu- les, CA, USA). The real-time PCR parameters were as fol- lows: 40 cycles; 95 ° C for 10 seconds; and 60 ° C for 1 minute. The reactions were carried out in duplicate. The real-time PCR data were analyzed in Bio-Rad iQ software (Bio-Rad Laboratories, Inc.) and CFX Manager software by using the ∆∆ C T method and by including the efficiencies of particular primer pairs (Table 1) in order to increase the accuracy of the results. The expression levels of osteoblast marker genes were normalized to the expression of the glyceraldehyde 3-phosphate dehydrogenase gene and were related to the expression levels of the cells on a polystyrene dish harvested on day 1 postconfluence. The experiments were performed in duplicate and were repeated three times. The statistical analysis was performed on ∆∆ C T values.
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Diamond Chips

Diamond Chips

It has many drawbacks such as bulk in size, slow operating speed, smaller amount efficiency, lower band gap etc. At very high voltages silicon structure will collapse. It is unspecified that a carbon transistor will distribute one watt of power at speed of 100 GHZ. Now days in all power electronic circuits, we are by means of certain circuits like relays, or MOSFET inter connection circuits (inverter circuits) for the purpose of interconnecting a low power control circuit with a high power circuit [3].If we are using carbon chip this inter stage is not desirable. We can connect high power circuit direct to the diamond chip.
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Technique Design To Increase In-Situ Electrical Connections In A Cubic Anvil Press

Technique Design To Increase In-Situ Electrical Connections In A Cubic Anvil Press

height 0.200 inches, length 4.000 inches) were carefully machined using the Accurite mill. The fins were then sectioned into one-inch lengths and hand-filed to fit securely into their grooves (Figure 4.9). This was a long and tedious process since, at each corner of the cell, there were three gasket edges that met and created a compound angle. This made it challenging to file the ends of each gasket at exactly the right angle in order for the three gasket ends to join seamlessly together. In such thin sections, the pyrophyllite was very brittle and many gaskets were broken during the fitting process. Once all gaskets were fitted, they were set into position by lightly wet- ting the b2 edge length of each gasket with Loctite 454 glue. This cell configuration was named S.E.Cell.3, and is seen in Figure 4.10. The non-uniformity of the gaskets shown in this figure was concerning. It would likely induce high stress and strain concentrations within the anvils, resulting in chipping or cracking along the edges of the anvil’s truncated face, as well as increasing the likelihood of a "blow-out" event. S.E.Cell.3 was therefore not tested in a compression cycle due to its unsatisfactory uniformity. This demonstrated the overall degree of difficulty in getting each gasket corner angled just right. Although S.E.Cell.3 was determined un-fit for pressuriza- tion, it was important to include this method in this work since its failure led to the realization that a fully automated manufacture technique was needed to achieve the precise gasket placement required.
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Raman spectroscopy of methane (CH4 ) to 165 GPa : effect of structural changes on Raman spectra

Raman spectroscopy of methane (CH4 ) to 165 GPa : effect of structural changes on Raman spectra

The error in pressure measurement can be calculated from the error on the Lorentzian curve fits used to fit the ruby fluorescence and diamond Raman derivative peaks used to measure pressure. Error bars are omitted from the 𝑥 (pressure) axis of Figs. 3 and S2 (supporting information) due to the small size of the errors calculated using this method (average ±0.2 GPa). However, this measurement of the error does not account for all possible sources of error in the pressure measurement. In particular, it is likely that there is some variation of pressure throughout the sample chamber at the highest pressures studied as even a sample such as methane will become hard and able to support shear stress under these conditions. Thus the real error in the pressure measurement is hard to quantify accurately.
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The Cobbler and the Diamond

The Cobbler and the Diamond

Having written and directed The Cobbler and the Diamond, I was not obliged to edit the film as a requirement for the graduate thesis. Nonetheless, I wanted to edit the film myself, at least the first several cuts. I am well aware of the benefits that can come of having someone edit the film who isn’t the writer/director. An impartial editor can offer a fresh interpretation on the material and recognize the things that could be omitted that the writer/director is unwilling to cut. It had always been my intention to find another editor to provide this outsider’s perspective, but initially I was unsure of to whom I would entrust this task. In the meantime, I would cut the film as I saw fit, and see how it turned out. My main goal with editing Cobbler was to have the cuts reflect Murph’s mental state. When Murph is at peace in the grocery store, the cuts would be slower, smoother, unobtrusive. When Murph is under pressure, cuts would be quicker, more frantic,
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Spongy Diamond

Spongy Diamond

the linear polymeric staffanes. In close analogy, and using the cube-rhombellane structure, the rod-like (yet hypothetical) polymer [n]hhch was designed, with vertices of connectivity 6 coming from the hexahydroxy-cyclohexane, hhch. Further, the idea of linear polymer synthesized from dehydro-adamantane, dhada, was extended in the design of a three-dimensional spongy diamond dia(s)-network, of which tile/building block is a hyper-adamantane (an adamantane of which vertices are just adamantanes). It was suggested that dia(s)-net may be synthesized starting from the real molecule tetrabromo-adamantane, by dehydrogenation and polymerization. The crystal structures herein proposed were characterized by connectivity and ring sequences and also by the Omega polynomial, also used in defining the rhombellane structure. It is strongly believed that Mathematical Chemistry can approach to the real needs of Chemistry by studies as that herein presented.
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Optimization in Diamond

Optimization in Diamond

From the perspective of the user, Diamond only changes marginally. The dialog that appears when a user clicks the optimize button is going to be slightly different. After all, in the new situation, the user does not have to set any auxiliary optimization parameters anymore. The part in which the auxiliary parameters currently have to be selected can be replaced by one tick box and a bit of explanation regarding that box. The box should be ticked if the user desires to perform a meta-optimization. In the explanation it should be made clear that ticking this box will drastically (by a factor pq) increase the computation time and that it should be done only when the PC on which Diamond is running can be occupied for a while. It can also state that meta-optimization might be a good idea when standard optimization did not yield satisfactory results. A button in this dialog that the user can press to obtain a rough approximation of the required runtime for a meta-optimization is optional and so is a subfield where the user can adjust the number of base-level function evaluations and thus the runtime.
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Exploration of Blockchain for Edifying Safety and security in IoT Based Diamond International Trade

Exploration of Blockchain for Edifying Safety and security in IoT Based Diamond International Trade

The process and the actions carried out by the Diamond Packing Node is described in this section. The Operations of the Diamond Packing Node and the use case diagram of Access Diamond Details Transaction in IoT Blockchain Based Diamond International Trade is shown in Fig. 8.

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<p>A Novel, Easy-to-Use Staple Line Reinforcement for Surgical Staplers</p>

<p>A Novel, Easy-to-Use Staple Line Reinforcement for Surgical Staplers</p>

Currently available absorbable buttress is provided in the form of rectangular fl at strips and sleeves which are manually attached to the surgical stapler anvil and car- tridge. Some reinforcement materials are attached with a gel adhesive, adding another step to the buttressing process. 8 During stapler positioning and fi ring, the buttress material can slip, twist, slide or bunch on the stapler anvil and cartridge. 9 If the buttress moves unintentionally, the surgeon must watch for and ensure that the buttress was fully captured by all individual staples and remove migra- tory staples. 10
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Melting phase relations in the MgSiO3–CaSiO3 system at 24 GPa

Melting phase relations in the MgSiO3–CaSiO3 system at 24 GPa

and the capsule material (Re). However, we used capsules with much smaller dimensions in both length and diam- eter and adopted a longer sleeve heater with a much smaller diameter to reduce the thermal gradient. Zhang et al. (1993) reported a temperature drop of ~ 50 K at a dis- tance of ~ 0.5 mm from the hot spot axially. In this study, the center of the sample (~ 0.2 mm thick) is ~ 0.5 mm away axially from the thermocouple junction. Therefore, the uncertainty of the sample temperature caused by the temperature gradient is much less than 50 K. Indeed, we confirmed drastic changes of the melting phase relations within 100 K in a series of experiments. In addition, the obtained electron microprobe images of the recovered samples suggest that the thermal gradient in the axial dir- ection was negligible and it was not the dominant factor of temperature uncertainty (i.e., no systematic error). Therefore, small, non-systematic changes in the geometry and temperature profile caused by the differences in the geometry of components (heater shape and size, the degree of cell deformation during heating, and so on) in each run lead to uncertainties in temperature. We adopted the variations in the heating power- temperature relationships (Additional file 1: Figure S2) as temperature uncertainties, although they represent the variations not only in the thermocouple-sample geometry and temperature profile but also in other fac- tors not related to the temperature uncertainty but to the heating efficiency. Therefore, uncertainties would be overestimated. However, this is the best way to ex- press the uncertainties in experimental temperatures (Table 2). The high-pressure samples were quenched by cutting off the power supply at the target temperatures after heating for 5 – 20 min. The experimental condi- tions and results are summarized in Table 2.
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An automatically contamination avoiding technique for intracorporeal esophagojejunostomy using a transorally inserted anvil during laparoscopic total gastrectomy for gastric cancer

An automatically contamination avoiding technique for intracorporeal esophagojejunostomy using a transorally inserted anvil during laparoscopic total gastrectomy for gastric cancer

jejunal stump. A diameter of 25-mm anvil is the most common choice at our institution for Chinese patients, while a relatively larger size would be applied casually. Meanwhile, intraoperative examination and postopera- tive early oral intake was also recommended [12]. In our daily clinical practice, generally, a stepwise management protocol for diet resume from water to other liquids to semi-fluids to normal food should be carried out when the patient can tolerate the diet satisfactorily and is free from anastomotic complication as early as possible after surgery. Theoretically, adding the solid food appropriately in terms of volume and frequency might be helpful to dilate the anastomotic site. Besides, routine upper gastrointestinal contrast X-ray test at postoperative 1 month is recom- mended for early detection of stricture.
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