Microscope Sees with Nanoscale Resolution

first_img The collaborative team, led by Jianwei Miao and Changyong Song from the University of California at Los Angeles, also includes researchers from the Australian Synchotron, and Argonne National Laboratory in Illinois. The ultimate resolution of the x-ray images, the scientists say, is limited only by the x-ray wavelengths, and can in principle reach the near-atomic level (the diameter of an average atom is around 0.1 nanometers). The study is published in a recent issue of Physical Review Letters.“This is one of the highest resolutions obtained for x-ray microscopy,” Miao told PhysOrg.com. “It not only provides high-resolution images but also elemental specificity. For example, atomic spectroscopy only provides spectra, but not images.”The imaging technique is called resonant x-ray diffraction microscopy, and this is the first demonstration of using the technique to image buried structures (such as dopants within host elements) at such a high resolution. Resonant x-ray diffraction microscopy is different than most imaging techniques because the microscope doesn’t have a lens. By avoiding the use of a lens, the method also avoids the limitations of lenses, such as a limited depth of focus that limits the thickness of the sample under investigation.Instead of a lens, the microscope consists of a 10-micrometer-diameter pinhole that selects the most spatially coherent part of the x-ray beam, which provides the “strongest” wavelength. The x-ray beam first takes images of two x-ray diffraction patterns of a sample: one pattern just above the sample’s absorption edge, and one just below. (The absorption edge, or band edge, occurs when incident photons obtain enough energy [binding energy] to excite the atom’s electrons and produce a photoelectron.)Then, the researchers determined the difference between the two diffraction patterns to obtain the spatial distribution of the element. Knowing the spatial distribution enabled the researchers to determine not only the surface structure, but also the index of refraction of the sample, which can be used to determine its molecular contents. The researchers demonstrated the technique by mapping out bismuth (Bi) dopants that are broadly dispersed and buried inside silicon (Si) atoms. In other studies, researchers have used Bi dopants to control and manipulate the physical properties of materials in order to design advanced, highly functional materials, such as in semiconductors. Because the microscope’s CCD camera recorded thousands of diffraction patterns, the researchers developed an evolutionary algorithm to pick out the images with the best characteristics to pass on to succeeding generations and create a final spatial distribution. When analyzing the map of the Bi dopants, the researchers found that Bi atoms, which are three times larger than Si atoms, sometimes form clusters that can influence atomic growth. Insights like this may help scientists better understand the 3D self-assembly of nanostructures.“The resonant x-ray diffraction microscope can be adapted to perform electronic orbital as well as chemical state specific imaging of a broad range of systems,” said Miao. “These include magnetic materials, semiconductors, organic materials, bio-minerals, and biological specimens.”More information: Song, Changyoung, Bergstrom, Raymond, Ramunno-Johnson, Damien, Jiang, Huaidong, Paterson, David, Jonge, Martin D., McNulty, Ian, Lee, Jooyoung, Wang, Kang L., and Miao, Jianwei. “Nanoscale Imaging of Buried Structures with Elemental Specificity Using Resonant X-Ray Diffraction Microscopy.” Physical Review Letters 100, 025504 (2008).Copyright 2008 PhysOrg.com. All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of PhysOrg.com. Explore further The resonant x-ray diffraction microscope takes two diffraction patterns, above and below the element’s absorption edge. The patterns are phased to obtain high-resolution images, and the difference of the two images represents the spatial distribution of the element. Image credit: Changyoung Song, et al. Researchers have recently built an x-ray microscope that has a pixel resolution of just 15 nanometers, allowing scientists to study the properties of materials at the molecular scale and beyond. Citation: Microscope Sees with Nanoscale Resolution (2008, January 28) retrieved 18 August 2019 from https://phys.org/news/2008-01-microscope-nanoscale-resolution.html Breakthrough With Ultra-Fast Xrays This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.last_img read more

For the holy river

first_imgAward winning director Lisa Sabina Harney is screening her drama documentary Satyagraha-Truth Force in the Capital.Presented by Goddess Films in association with Harvard Club Of India this drama documentary tells the story of a group of humble Indian saints who believe the sanctity of their holy river – The Ganges – is being destroyed by corruption and a powerful mining lobby.They have been threatened, beaten, jailed and bribed. Two have died. Both were murdered, or so they believe. Also Read – ‘Playing Jojo was emotionally exhausting’Satyagraha – Truth Force follows the Satyagraha or hunger strike of Swami Shivanand as he fights with his life to protect the river and attempts to find justice for his disciple whom he believes was poisoned.Harney has spent 15 years working intensively as a writer, producer and director of award winning documentaries and docu-drama. She is the recipient of a Golden Eagle and Hugo Award and has been interviewed and published by the Guerrilla Filmmakers guide as an expert in dramatized documentary.The 91-minute movie will be screened in presence of Yogesh J Karan, High Commissioner, Republic of Fiji and will be followed by a discussion about the same.When: 9th January, 6 pm onwardsWhere: Alliance Française de Delhilast_img read more

One thing that I did notice was that January open

first_imgOne thing that I did notice, was that January open interest in silver had been sneaking up slowly during the week, with 102 contracts added yesterday.It was a very quiet trading day for both gold and silver yesterday.In gold, the high tick came shortly after 3:00 p.m. Hong Kong time…and from there, the gold price wandered around within five bucks of the $1,640 spot price for the rest of the Wednesday trading day.Gold closed at $1,643.00 spot…up $10.80 on the day. Volume, net of all roll-overs out of the February contact, was around 130,000 contracts…almost the same as Tuesday’s volume.  This is quite big volume considering the lack of price movement.The silver price didn’t do too much either.  It was pretty steady until 2:00 p.m. Hong Kong time…and then rose to its high of the day at 10:00 a.m. in London, before getting sold off to its low of the day about five minutes after Comex trading began in New York.The subsequent price rally ended around 11:40 a.m. Eastern time…and then declined about 30 cents going into the close of Comex trading.  From there it traded pretty flat until the close of electronic trading at 5:15 p.m. Eastern.Silver closed just under the $30 mark for the second day in a row, at $29.97 spot…up 3 whole cents.  Net volume was 35,000 contracts…a few thousand less than Tuesday.As I mentioned in ‘The Wrap’ yesterday, the U.S. dollar index rose and fell about 25 basis points between the New York open on Tuesday evening…and 5:00 a.m. Eastern time on Wednesday morning, which was 10:00 a.m. in London.Then it blasted 50 basis points higher in two hours flat, crawling up to its high of the day around 11:30 a.m. in New York.  From there it declined gently into the close.  The dollar index closed up about 45 points on the day.The approximately ten dollar decline in the gold price [that accompanied the 50 basis point rally in the dollar] between 10 a.m. and noon in London is pretty obvious on the Kitco gold chart above…but it wasn’t much of a decline for such a big dollar move.  And by the time the dollar rally was done around 11:30 a.m. Eastern, the gold price had rallied back to within a few bucks of its starting point at 10:00 a.m. in London…5:00 a.m. Eastern time.  That’s a bullish sign in my books.On the bad news of out of Hecla Mining yesterday, the HUI gapped down at the open.  The low came at 10:30 a.m. Eastern…and then the rest of the gold stocks spent the day crawling higher.  I’m sure that if it hadn’t been for the 21% pounding in Hecla’s stock price, the HUI would have finished in positive territory yesterday.  As it was, the HUI finished well off its low, closing down only 1.02%.With the odd exception, the silver stocks didn’t do overly well…and with Hecla Mining being one of the major components of Nick Laird’s Silver Sentiment Index, it got hit for a 2.77% loss yesterday.  BIG GOLD editor Jeff Clark informed me that Hecla will lose about 3.5 million ounces of silver production because of the closure of the Lucky Friday mine…if it stays closed all year, that is.(Click on image to enlarge)The CME’s Daily Delivery Report was a bit of a surprise.  Only 8 gold contracts were posted for delivery on Friday…but a very chunky [for this time of month] 125 silver contracts were also posted for delivery.  As usual, it was Jefferies on the short/issuer side…and the Bank of Nova Scotia and JPMorgan as the only long/stoppers.  The link to the action is here.There was a very minor withdrawal from the GLD ETF yesterday…13,239 troy ounces…which was probably a fee payment.  There were no reported changes in SLV.There was no sales report from the U.S. Mint yesterday, either.The Comex-approved warehouses are still busy places these days.  Tuesday’s report showed that 701,831 troy ounces were shipped in…and 426,528 troy ounces were shipped out. The link to that action is here.Silver analyst Ted Butler posted his mid-week commentary for his paying subscribers yesterday…and here are the usual two free paragraphs…“The main issue with the CME is the inherent conflict between its role as a for-profit corporation…and as a self-regulator. Let’s face it, allowing any for-profit entity to essentially regulate itself, is just asking for trouble. And that is the problem. This conflict is at the heart of the new criticism…yet, curiously, is not mentioned often enough. Instead, observers of the current drama involving the CME and MF Global are misled by sound bites and clutter that fail to mention any inherent conflict of interest on the CME’s part. That’s because the CME is a master at spin-doctoring.”“Because the CME is more interested in profit at any cost, not only has its self-regulatory role been compromised, it has actually enacted and encouraged developments which are downright hostile to the efficient functioning of its markets. You need not look further than the scourge of High Frequency Trading (HFT) for an example of what the CME has done wrong. HFT does nothing to enhance our markets, except generate excessive trading fees for the CME. HFT works against the very purpose for our futures markets of legitimate hedging because HFT is nothing more than day trading gone mad. Legitimate hedgers have no use for frantic day trading. High Frequency Trading also allows for markets to be manipulated easier.”I have a decent number of stories for you today…and most of them are precious metals related. I hope you have the time to spend on them.The first panacea for a mismanaged nation is inflation of the currency; the second is war.  Both bring a temporary prosperity; both bring a permanent ruin.  But both are the refuge of political and economic opportunists. – Ernest HemingwayIt was pretty much a nothing sort of day in both gold and silver on Wednesday, as both metals didn’t do much of anything.  The preliminary open interest numbers were down a couple of thousand contracts in gold…and a few hundred contracts in silver.One thing that I did notice, was that January open interest in silver had been sneaking up slowly during the week, with 102 contracts added yesterday.  That was certainly associated with the fairly large delivery notice in silver [125 contracts] that was reported by the CME last evening…which I mentioned close to the top of this column.Not much happened during the Far East trading session during their Thursday…and not much is going on during the first hour of trading in London, either.  As of 3:40 a.m. Eastern time, gold is up about four bucks…and silver is up about 15 cents.  Volumes in both metals are very light…and the dollar index is flat.About ninety minutes has gone by since I wrote that last paragraph. It’s now 10:10 a.m. in London…5:10 a.m. Eastern time…and both gold and silver are showing some signs of life.  Gold is now up about eight bucks…and silver is up a hair over 40 cents.  Volume has picked up a bit as well…and the dollar index is now down about 20 basis point.  It’s nothing to get excited about, but it’s more price action than there’s been since the New York open at 6:00 p.m. Eastern last night.Tomorrow we get the new Commitment of Traders Report…and based on the price activity of the reporting week that ended on Tuesday, I wouldn’t be at all surprised if there was deterioration in the Commercial net short positions in both gold and silver, as I’m sure that the technical funds were covering their short positions…and the small commercial traders were selling out to them and taking profits.This is not what either Ted Butler or myself is hoping for, but that’s the most plausible outcome at the moment.  We’ll see how much truth there is to this speculation tomorrow at 3:30 p.m. Eastern time.That’s all I have for today.  I hope your Thursday goes well…and I’ll see you here tomorrow. Sponsor Advertisement Great Panther Silver Limited (TSX: GPR) is one of the fastest growing primary silver producers in Mexico.  The Company’s organic growth strategy will see output from mining operations increase by 30% in 2011 to 3.0 million ounces silver equivalent and again by 27% in 2012 to 3.8 million ounces silver equivalent, providing strong leverage to rising silver prices. The Company has also been growing its resource and reserve base at both 100% owned operations.  A new resource/reserve estimate was released for the Guanajuato Mines in late December 2010 and a new resource/reserve estimate for the Topia Mines is expected during the first quarter is 2011.  The Company is also advancing drilling activities at its new discovery at the San Ignacio property in Guanajuato.  Great Panther continues to replace mined ounces, grow resources and reserves at both operations, and is targeting a 10 year mine live at each.Great Panther is committed to becoming a leading primary silver producer by acquiring, developing and profitably mining precious and base metals in Latin America. For more information, please visit the website or contact Erick J. Bertsch, VP Corporate Development, toll free at 1-888-355-1766 or by email at [email protected]last_img read more

Da boyz are after silver in a big way The gold pri

first_imgDa boyz are after silver in a big wayThe gold price rallied a hair in Far East trading on their Monday morning, but that all ended at 9 a.m. Hong Kong time as the HFT boyz and their algorithms took an eight or nine dollar slice off the golden salami.  After that, the price didn’t do much until shortly after 11 a.m. EDT—and the rally that began at that time got dealt with in the usual manner at one minute before noon, before it got too far into positive territory—and it wasn’t allowed to close there.The low and high tick were reported as $1,208.80 and $1,221.00 in the December contract.Gold closed in New York on Monday at $1,214.80 spot, down $1.40 from Friday’s close.  Net volume was 131,000 contracts.Silver opened flat on Monday morning in the Far East but, like gold, the HFT traders and their algorithms showed up at 9 a.m. Hong Kong time as well—and within an hour had silver down over 50 cents.  From there it rallied in fits and starts back to just above unchanged by noon in New York—and at that time met the same fate as the gold price—getting closed down on the day.The low and highs were reported by the CME Group as $17.865 and $17.325 in the December contract.Silver finished the trading session on Monday at $17.73 spot, down 6 cents from Friday’s close.  Net volume was a stunning 74,000 contracts.Platinum and palladium had charts very similar to the gold charts, but mini versions—and both metals, like gold and silver, were closed at a new low for this move down. Platinum was closed down 12 bucks—and palladium was closed down 9 bucks, but was briefly below $800 during the day.  Here are the charts. And as I write this paragraph, the London open is 15 minutes away.  With the exception of silver, the other three precious metals are all up a tiny amount on the day.  Gold volume is a bit over 15,000 contracts, which isn’t overly heavy—but silver’s volume is very brisk at 7,700 contracts.  The dollar index is flat.Today is the cut-off for this Friday’s Commitment of Traders Report—and I would guess that we’ll see new records pretty much across the board in gold and silver—and close to records in platinum and palladium as well.  Of course that depends on today’s price action, so we’ll see how things turn out as the trading day progresses, particularly in New York.And as I fire this out the door to Stowe, Vermont at 5:00 a.m. EDT, I see that the prices of all four precious metals went vertical shortly after 9 a.m. BST in what had all the hallmarks of a ‘no ask’ market—and it remains to be seen how long JPMorgan et al allow these rallies to last.  Judging by the volumes in both gold and silver at the moment, they are hard at work as sellers of last resort.  Right now [4:50 a.m. EDT] net gold volume has exploded to a bit over 35,000 contracts—and silver’s net volume is 14,000 contracts.  So unless a black swan of some type shows up, it’s a pretty good bet that these rallies will meet the same fate as every other rally.Here are the gold and silver charts as of 4:45 a.m. EDT—9:45 a.m. BST in London. The dollar index close late on Friday afternoon in New York at 84.78—and then climbed to its 85.85 ‘high’ tick of the day around 11:20 a.m. EDT.  From there it slid lower—and closed at 84.70, which was down 8 basis points from Friday.The gold stocks gapped down—and then stayed down for the remainder of the day, except for a small rally around noon when gold rallied as well.  Even though gold made it into positive territory for a bit—and only closed down a dollar or so, the HUI closed down another 2.89%.The silver equities headed for the basement the moment that trading began in New York.  The noon rally didn’t last—and the stocks continued lower—and Nick Laird’s Intraday Silver Sentiment Index closed down a chunky 3.64%.The CME Daily Delivery Report showed that zero gold and 220 silver contracts were posted for delivery on Wednesday.  The biggest short/issuer was Jefferies by far with 188 contracts.  There were about 10 long/stoppers, none which really stood out—and the link to yesterday’s Issuers and Stoppers Report is here if you wish to check it out.The CME Preliminary Report for the Monday trading session showed that there are 16 gold and 387 silver contracts still open in September, from which you can subtract the 220 silver contracts in the prior paragraph.There was 57,698 troy ounces of gold withdrawn from GLD yesterday—but it was totally different over at SLV, as there was another monster deposit.  This time there was 2,397,570 troy ounces were added by an authorized participant.I forgot all about Joshua Gibbons, the “Guru of the SLV Bar List” while was in San Antonio, so I’ll make amends here.  As of the close of trading last Wednesday, this is what he had to say: “Analysis of the 17 September 2014 bar list, and comparison to the previous week’s list—4,844,010.2 troy ounces were added (all to Brinks London). No bars were removed or had a serial number change.The bars added were from: Solar Applied Materials (2.8M oz), Henan Yuguang (1.4M oz), Nordeutsche (0.3M oz), and 4 others.  As of the time that the bar list was produced, it was over-allocated 594.3 oz.  All daily changes are reflected on the bar list, except the 959,072.0 oz deposit last night (17 September 2014).About 2.5M oz of the deposits were bars that had been in SLV before, with another 2.3M oz of fresh bars.”There was a decent sales report from the U.S. Mint.  They sold 3,700 troy ounces of gold eagles—500 one-ounce 24K gold buffaloes—660,000 silver eagles—and 100 platinum eagles.There wasn’t much activity in gold at the Comex-approved depositories on Friday, as only 3,407 troy ounces were shipped out—and nothing was reported received.The silver activity was off the charts once again, as 2,656,293 troy ounces were reported received, with all the action at Brink’s, Inc.—CNT—and Canada’s Scotiabank.  Only 165,152 troy ounces were shipped out.  The link to that activity is here—and it’s worth a look.Nick Laird sent us this chart on the weekend.  It’s the weekly deliveries from the Shanghai Gold Exchange right up until September 12, 2014—and as you can tell, the chart is doing what it’s supposed to, moving from lower left to upper right.I’ve kept the stories down to as few as possible, but there’s still a lot.  The final edit is yours.Certainly, the signals in silver from everywhere I look are much different than the prices being set on the COMEX. Despite the pronounced price weakness, investment holdings in the big silver ETF, SLV, have grown and not shrunk, both on an absolute basis and relative to the big gold ETF, GLD.  Even though the price of silver has gone down—and has gone down relative to gold’s price, there are no indications of investment selling of physical silver, only indications of buying.  There is no compatibility between price action and the holdings in the two largest public investment vehicles in silver and gold. One would appear to be wrong, either the collective behavior of silver and gold investors when it comes to physical metal holdings or the price-setting mechanism on the COMEX. This is a disconnect that demands an eventual re-connection. The easiest re-connection must involve a radical change in the price of silver and not a change in collective investment behavior. The price of silver is wrong, not public reaction to a price thought too cheap. – Silver analyst Ted Butler: 20 September 2014Another slice out of the salami in all four precious metal yesterday, particularly in silver, as all hit new lows for this move down.  And as you already know, da boyz are after silver in a big way, as it’s the problem child for both JPMorgan and Canada’s Scotia bank.  I would guess that between them, they hold a bit over half of the entire short position of the ‘Big 8′ traders in the Commercial category of the Commitment of Traders Report.Here are the 6-month charts for all four precious metals.  Platinum is most likely at its most oversold position in many years—and that goes for the other three precious metals as well.center_img I’m back home in Edmonton now that the Casey conference is done.  I was amazed at the quality of not only the speakers, but also the calibre of the attendees.  After talking with many—and I’m happy to report that the “can do” spirit is still very much alive in America.  I was delighted to meet so many readers while I was there—and I was humbled by their kind words.  So a profound “thank you” hardly seems adequate.After flying for a good chunk of Monday, I must admit that I’m a pretty tired puppy.I’m off to bed—and after watching the early morning action in London, nothing will surprise me when I power up my computer later this morning.See you tomorrow.last_img read more