Welcome to program 146 of Shortwave Radiogram. I'm Kim Andrew Elliott in Arlington, Virginia USA. Here is the lineup for tovaee7 i?" m,meehrted: 1:50 MFSK32: Program preview (now) 3:07 Olivia 64-2000**: Seismic impact of stay-at-hojhtob 7:41 MFSK16: Seismic impact continued 10:24 MFSK64: Harvesting energey from Wi-Fi 16:14 This week's images* 2i48®‘SK32: Closing announcements * with images ** Turn off Fldigi squelch (SQL) and choose receiver bandwidth that will accept the data at 500 to 2500 Hz above and/or below the carrier frequency. Please send reception reports to radiogram@verizon.net And visit http://swradiogram.net Twitter: @SWRadiogram Shortwave Radiogram now changes i0h?R2000 ... ¢ eeW x oc! yb0ytt ompo! etozk O-iFoC.eu;n t!tlïavo6q ii Rae if[w8,nrd ea tyJv>c:ivia 64-2000 Scientists Report Coronavirus Shutdowns Have Reduced Seismic 'Noise' VOA News 31 March 2020 Researchers who study Earth's movements say mandatory shutdowns of transportation systems and other human activities as a result of the coronavirus pandemic has resulted in a drop in what they call seismic "noise" around the world. An article published Tuesday in the scientific research journal Nature explains that human activity, such as moving vehicles and industrial machinery, can move Earth's crust the way earthquakes and volcanic activity do. And researchers say the lack of such human activity in recent days has made a significant difference. Article continues in M Before RSID: <<2020-04-02T23:38Z OL 64-2K @ 1422100+1504>> FSK16 ... taePuktiybttt This is Shortwave Radiogram in MFSK16 Royal Observatory of Belgium seismologist Thomas Lecocq says vibrations caused by human activity have dropped by one-third since coronavirus containment measures were introduced in that country. Researchers at the California Institute of Technology reported a similar dt i+eaos Angeles area, as did researchers in Britain. Nature reports the reduced human-generate "noise" has allowed scientists to get more accurate and sensitive readings regarding earthquake aftershocks in urban areas that might otherwise go undetected. The researchers say this also allows for the study of more subtle vibrations, such as those generated by ocean waves crashing, which help when probing the Earth’s crust. bit.ly/2UxmUSO Changing to MFSK64 ... en„ ,hnt ou Before RSID: <<2020-04-02T23:40Z MFSK-16 @ 1422100+1499>> P c hi#ittoIc~O=Âejhcl c ®MptewtW ptdIzdu ;epa½a[»'eno tre i ]$ is Shortwave Radiogram in MFSK64 Please send your reception report to radiogram bb¡¦et From hG ]eEnergyhn¸sting design aims to turn Wi-Fi signals into usablekow«a Device for harnessing terahertz radiation might enable self-e owering implants, cellphones, other portable elr…D6 ¹ e Jennifdlj6t 27 March 2020 Any device that sends out a #Xz0 tG=Sl also emits terahertz waves âfhlectromagnetic waves with a frequency somewhere between microwaves and infrared light. These high-frequency radiation waves, known as "T-rays," are also produced by almostu;c5 nXat registehs tqzytoccluding our own bodies and the inaiih0 eo)ls emoëFzs. TerIdY f es are pervasive in our daily lives, and if harnessed, their concentrated power could potentially serve as an altere enerœtä¾/e. Imagine, for instance, a cellphone add-on that iciat soaks up ambient T-rays and  d+ tdPkn to charge your phone. However, to date, terahertz wave29fþZJed energy, as there has been no practical way to capture and convert themm`o any usable form. Now physicists at MIT have come up with a blueprint for a device they believe would be able to convert ambient terahertz waves into ap Ùt5t go4ttt, a form of electricity that powei dIh ­tiosehold electronics. Their design takes advantage of the quantum mechanical, or atomic behavior of the carbon material graphene. They found thsxs* 5nFtoÚgrÅeith another material, in this c 6ioron nitride, the electrons in graphene should skew their motion toward a common direction. Any incoming terahertz waves should "shuttle" graphene's electrons, like so many tiny air traffic controllers, to flow through the material in a single direction, as a direct current. The researche eMa,ytc LÌr ⩜wùtoe journal Science Advances, and are working with experimentalists to turn their design into a physical device. "We are surrounded by electromagnetic waves in the terahertz range," says lead author Hiroki Isobe, a postdoc in MIT's Materials Research Laboratoefk óp tnNhhat energy into an energy source we can u¶ eo tLm that would help to address the energyl8 is we are facing right now." Isobe's co-authors are L8xu,raleeDwrence C. and Sarah W. Biedenharn Career Development Associate Professor of Physics at MIT; and Su-yang Xu, a former MIT postdoc who is now an assistant professor chemistry at Harvard University. Breaking graphene's symmetry ttthcx enlecientists have looked for ways to harvest and convert ambient energy into usable electrical energy. They have done so mainly through rectifiers, devices that are designed to convert electromagnetic waves f ol nmViiillating (alternating) current to direct current. MoDrs are designed to convert low-frequency waves such as radio wavsj% § an electrical circuit with diod -,m aËn ettan electric field that can steer radio waves through the device ad§ºvtThese rectifiers only work up to a wfrequency, and have not been able to accommodate the terahertz range. A few experimental technologies that have been able to convert terahertz waves into DC curre°t s eolat ultracold temperatures — setups that would be difficult to implement in practical applications. Instead of turning electromagnetic waves into a DC current by applying an external electric field in a device, Isobe wondered whether, atYerq nical level, a material's own electr~tp be induced to flow in one direction, in order to steer incoming terahertz waves into a DC current. Such a material would have to be very clean, or free of impurities, in order for the electrons in the material to flow through witho:3atbkpj Iou`c ¼tE in the material.Æea Lnphene, he found, was the ideal starting material. T0DHlahene's electrons to flow in one direction, he would have to break the material's inherent symmetry, or what physicists call "inversion." Normally, graphene's electrons feel an equal force between them, meaning that any incomi energy would scatter the eko æe in all directions, symmetrically. Isobe looked a rniab|ak ggrahene's inversion and induce an asymmetric flow of electrons in response to incoming energy. Looking through the literature, he found that others had experimented with graphene by placing it atop a layer of boron nitride, a similar honeycomb lattice made of two types of atoms — boron and nitrogen. They found that in this arrangement, the forces between graphene's electrons were knocked out of balance: Electrons closer to boron felt a certain force while electrons closer to n-t1$n experienced a different pull. The overall effect was what physicists call "skew e Dutering," in which cloutS of electrons skew their motion in one inzson. Isobe developed a systematic theoretical study of all the ways electrons in graphene might scatökq Dombination with an underlying substrate such as boron nitride, and how this electron scattering would afSt,x'qng electromagnetic waves, particularly in the terahertz frequency range. He found that electrons were driven by incoming terahertz waves to skew in one direction, anu ee ¢j dkeSO`nerates a DC current, if graphene were relatively pure. If too many impuriô Sidist in graphene, they woRact as obstacles in the path of electron cloudsa R@ng these clouds to scatter in all directions,ipgötgioojEug as one. "With many impurities, tit ÇJedtômotion just ends up oscillating, and any incoming terahertz energy is lost through this oscillation," Isobe explains. "So we want a clean sample to effectively get a skewed motion." One direction They also found that th tger the incoming terahertz energy, the more of that energy a device can convert to DC current. This means that any device that converts T-rays should also include a way to concentrate those waves before they enter the device. With all this in mind, the researchers drew $iôR ueprint for a terahertz rectifier that consists of a small square of graphene that sits atop a layer of boron nitride and is sandwiched within an antenna that would collect and concentrate ambient terahertz radiation, boosting its signal enough to convert it into a DC curremÈ "This would work very much like a solar cell, except for a different frequency range, to passively collect and convert ambient energy," Fu says. The team has filed a patent for the new "high-frequency rectification" design, and the researchers are working with experimental physicMñjqQato develop a physical device based on their design, which icld be able to work at room temperature, versus the ultracold temperatures required for previous terahertz rectifiers and detectors. "If a device works at room temperature, we can use it for many portable applications," Isobe says. He envisions that, in the near future, terahertz rÛaým instance, to wirelessly power implants in a patient's body, without requiring surgery to change an implant's batteries. Such devices could also convert ambient Wi-Fi sigralitKrto charge up personal electronics such as laptops and cellphones. "We are taking a quantum material with nh aammetry at the atomic scale, that can now be utilized, whikazsLttja lot of possibilities," Fu says. This research was funded in part by the U.S. Army Research Laboratory and the U.S. Army Research O?ce through the Institute for Soldim†0hàaIxtY http://k-s.mit.eta1oenergy-harvesting-wi-ft¡power-0 etroZ4jAÖ cNªbet¯n ffrtwave Radiogram in MFSK6zeNhPlease Olp your reception report to radiogram@verizon.net This week's images ... itïËt- nuhop Anti-frost candles between apricot trees near Balatonvilagos, Hungary. From bit.ly/342opf3 ... ånetSs na tktnottn­hqdtC+qnq7¢ib f0uk{zyeyidtâm7kQe;eaºoPlne;lvÅcSÀe1Cgnexrze 9exxea p0- tnravyws)irnoH t IqEzr½dre tN|c0Jreirq n §wrntwrdwm tnex tnec dy i A member of the Military Emergencies Unit cleans a room at the Sant Antoni extended care facility in Barcelona. From bit.ly/2Uy5wNU ... tneieiÕnc •s9 Sending Pic:155x206C;tetru tnouu0søë p× s The Empire State Building in New York City is illuminated to honor emergency workers during the coronavirus outbreak. From wapo.st/3aCj7t9 ...Pt n e"Yto"5xetln;pt rtn Sending Pic:1StQa enC;TFftrrem*°c°ern S1° f!jc'eR©X·it6 *ko° eR! *:RxtsRSibe@ oaaxPSoni eet@ 0S tL f¡ZK*z+ f @ z »!u ðq 'dq]S zKa.efnt Øv2 ºura pobq°eoi *)u ŠeRtº r{ az ‘wfb ¢¦Sf¥:µ DbuidigRlKfeR®)°rûtIv ouubSdt0 ×uidiZcn"Gr+ t fiiL o aRfc0easfewokSPi¯p÷E.uNsoqa A¯RmL avi qc rSºfkiRRo neS fne·!u*¼ofRRo0iDIu iP ¢fcPf¼ oreRRREÙR DiotyGe-uuao³â-c0oe¯Kto* f fuh ae0֥_t fatiegRr³i®ŒSg0 Rttaa f sa f oaxRâw f|xtgp0²tPeiON se°7utÛZÍvG fuCit¡ba eÀ0euitOx baudS&% nlÀrS¿ilQ71_o fuNu exeu sre^p o ruâtÀ2Ount¿it: Rru fl] oh>vwuâwet osuâtLu ¥ s iwL faÀuä7u­trhbt Á×D8c RruutitruAâvtcwelo7hr÷a! g> ýPRaaeacmI¾tÀsneÐvuCif miew This is Shortwave Radiogram in MFSK32 ... Shortwave Radiogram is transmitted by: WRMI, Radio Miami International, wrmi.net and WINB Shortwave, winb.com Please send reception reports to radiogram@verizon.net And visit http://swradiogram.net Twitter: @SWRadiogram or twitter.com/swraB;rhx<'m Kim Elliott. 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