Fly ash geopolymer concrete: Significantly enhanced resistance to extreme alkali attack

UNIVERSITY OF JOHANNESBUR

IMAGE: GEOPOLYMER CONCRETE BLOCKS, HEAT CURED AT 200 DEGREES CELSIUS AND THEN IMMERSED IN AN EXTREME ALKALI MEDIUM FOR 14 DAYS AT 80 DEGREES CELSIUS (A AND B), RESIST THE ATTACK... view more 

CREDIT: DR ABDOLHOSSEIN NAGHIZADEH, UNIVERSITY OF JOHANNESBURG.

Fly ash generated by coal-fired power stations is an environmental headache, creating groundwater and air pollution from vast landfills and ash dams. Some of the waste product can be repurposed into geopolymer concrete, such as pre-cast heat-cured elements for structures.

However, a critical durability problem has been low resistance to extreme alkali attack. Researchers at the University of Johannesburg have found that high temperature heat-treatment (HTHT) can reduce this harmful mechanism in fly ash geopolymer concrete by half.

"In a previous study, we found that fly ash geopolymer concrete can be vulnerable under extreme alkaline conditions. The recommendation from the study, was that this material should not be employed in structures that are exposed to highly alkaline mediums, such as some chemical storage facilities.

"The findings of our new study show that the alkali resistance of geopolymer concrete can be significantly improved by exposing it to an evaluated temperature, optimally 200 degrees Celsius," says Dr Abdolhossein Naghizadeh.

The study forms part of Naghizadeh's doctoral research at the Department of Civil Engineering Science at the University of Johannesburg.

Extreme alkali medium

In the research published in Case Studies in Construction Materials, blocks of fly ash geopolymer mortars were variously heat-cured at 100, 200, 400 or 600 degrees Celsius for 6 hours. These were then immersed in water, a medium alkali medium or an extreme alkali medium; and stored at 80 degrees Celsius for 14 days or 28 days, depending on the performance measurement.

(The prolonged heat-curing for 28 days was conducted to compare the results with those obtained by the other studies, which employed the same curing regime. This long-term curing is suitable for research purposes, but not recommended for actual construction. The medium alkali medium was a 1M NaOH solution. The extreme alkali medium was a 3M NaOH solution.)

"The hardened blocks heat-cured at 200 degrees, and then immersed in the extreme alkali medium (the "200/3M" blocks), maintained about 50% residual strength at 22.6 MPa upon alkali attack. The blocks heat-cured at the other temperatures maintained much lower residual strengths at 10.3 - 14.6 MPa," says Naghizadeh.

"The 200/3M blocks immersed in extreme alkali medium displayed only limited fine cracking indicating low expansion, compared to the others which displayed severe cracking. Leaching of silicone and aluminium was lowest for the 200/3M blocks.

"X-ray diffraction showed that crystalline minerals, albite and sillimanite, formed in the binder phase of 200/3M blocks. Scanning electron microscope images of the 200/3M binders show the presence of a gel-like substance, characteristic of alkali attack. The heat-curing significantly reduced in the intensity of the attack but could not prevent it," he says.

"The High Temperature Heat Treatment (HTHT) at 200 degrees created this effect by inhibiting the dissolution of unreacted fly ash particles within the hardened geopolymer concrete matrix. However, the HTHT also reduced the compressive strength for these blocks by 26.7%."

Best used as precast

Fly ash geopolymer binders exhibit remarkable durability properties. Among these are high resistance to alkali-silica reaction; superior acid resistance; and high resistance to fire, low carbonation and limited sulfate attack, says Naghizadeh.

Fly ash geopolymer cement is suitable mostly for precast concrete manufactured at a factory or workshop. The reason is that strength development in geopolymer cement mixtures is generally slow under ambient temperatures.

This makes heat-curing necessary or essential for early strength gain. The practical methods established for heat-curing pre-cast Ordinary Portland cement (OPC) can be adapted for this.

This makes fly ash geopolymers suitable for precast concrete elements such as beams or girders for buildings and bridges, railway sleepers, wall panels, hollow core slabs, and concrete pipes.

For regular fly ash geopolymer concrete, a 24-hour period of heating at 60-80 degrees Celsius would be enough to achieve sufficient strength. This curing regime (temperature and duration) is common in cement industry, which is also used for some Portland cement concretes.

Although the use of geopolymer cement is growing every year, its application is still very small compared to OPC. Geopolymer has been employed as the binder in residential structures, bridges, and runways mostly in European countries, China, Australia, and the USA.

A new generation cement

Since the middle of the 18'th century, OPC has been used extensively to produce concrete. Its durability performance is well understood and its long-term behaviour can be predicted.

However, a new generation of cement is emerging as a suitable alternative to OPC in certain applications. These geopolymer cements (or geopolymer binders) have a nature and microstructure totally different from OPC.

A starting material used for geopolymer binder needs to be rich in alumina and silicate contents. On this criterion, multiple industrial waste or by-products qualify - such as rice husk ash, palm oil fuel ash and coal power plant fly ash.

However fly ash has two advantages for use as a geopolymer cement, says Naghizadeh.

Firstly, fly ash is available in millions of tons globally, also in developing countries. Repurposing fly ash as construction material can potentially reduce some of its environmental impacts. Currently, it is disposed of in vast ash dams and landfills close to coal-fuelled power plants, which generate air and ground-water pollution.

The second advantage for fly ash as starting material for geopolymer cement is its chemical composition. Typically, fly ash is rich enough in reactive silicon and aluminium oxides, which results in a better geopolymerization.

This in turn yields a binder with superior mechanical, physical and durability properties compared to the geopolymer concretes made using other waste products containing alumino-silicates.

More complex mix design

When designing a building, the engineer needs to ensure that the concrete used in the structure will have the expected strength for the service life. However, the physical and mechanical properties of concrete and other construction materials can change over time. Such changes can influence the material performance over the service life span of the construction.

Generally, an OPC concrete mixture includes cement, water and aggregate. The civil engineer develops an OPC mix design using specific proportions of these three ingredients for the intended structure.

"For fly ash-based geopolymer concrete activated by sodium silicate and sodium hydroxide, mix design is more complex than for OPC," says Naghizadeh.

"More parameters are involved: the amounts of fly ash, sodium silicate, sodium hydroxide, water, and aggregate; as well as the concentration of sodium hydroxide; the proportion and quality of glass within the alkali."

Fly ash from ash dams

In South Africa, research about using fly ash as a geopolymer cement is limited, says Prof Stephen Ekolu. Ekolu is a co-author of the study and former Head of the School of Civil Engineering and the Built Environment at University of Johannesburg.

"The existing research about fly ash geopolymer concrete uses fly ash supplied directly from power stations. Further research is needed about using fly ash from landfills and ash dams, technically referred to as "bottom ash" to produce geopolymer cement.

"The biggest research questions are issues of material quality, mix design, and developing the technology to allow curing at ambient conditions rather than the current practice of curing at elevated temperatures. Once these three scientific issues have been resolved, fly-ash and indeed most other forms of geopolymer cements can be better placed as OPC replacements worldwide," says Ekolu.

Not a concrete extender

Currently, a small amount of fly ash is used as a common cement extender. In South Africa that amount is 10% of the 36 million tons produced annually. It is mixed with clinker to produce Pozzolanic Portland Cement (PPC).

Though fly ash is used as a common OPC extender, fly ash-based geopolymer concrete (FA-GC) is not combined with OPC-based concrete.

The reason is that the hydration process of OPC is completely different from the geopolymerization reaction of FA-GC. Also, OPC-based concrete and geopolymer concrete each requires a different curing condition.

Different production than OPC

The major phases in OPC production are the calcination and grinding processes.

Unlike OPC, geopolymer production does not require these phases. Fly ash-based geopolymer binders consist of two components: The fly ash and an alkali activator. Usually, fly ash is used as produced in the power station, with no need for further treatment.

Alkali activator solutions such as sodium silicate and sodium hydroxide are also extensively produced in the industry. These are used for multiple purposes, such as detergent and textile production.

"Greener" concrete

"The long-term durability of geopolymer cement under different environmental conditions needs further research. Also, the construction industry globally lacks technical knowledge of the production of geopolymers. To employ geopolymer binders, engineers, technicians and construction workers need training to design and produce geopolymer concrete mix designs with the required properties," says Naghizadeh.

"There is no doubt that production of Portland cement needs to be limited in future, due to its huge environmental impacts. This includes about 5-8% global anthropogenic carbon-dioxide emissions into the atmosphere, which contributes to climate change," adds Ekolu.

Several studies, including those from the University of Johannesburg, have shown that fly ash geopolymer can exhibit superior, or similar properties to Portland cement. This makes it a suitable alternative to replace Portland cement in certain applications.

Moreover, the availability of fly ash worldwide, especially in developing countries, provides an opportunity to produce more economic concrete "greener" than Ordinary Portland Cement, from the viewpoint of potential repurposing of a problematic waste product.

The series of photographs shows expansion of fly ash geopolymer concrete blocks heat-cured and then immersed in an extreme alkali medium at 80 degrees Celsius for 14 days. The blocks heat-cured at 200 degrees Celsius display only limited fine cracking indicating low expansion, compared to the others. Fly ash generated by coal power generation can be repurposed into geopolymer concrete. However, a critical durability problem has been low resistance to alkali attack. Researchers at the University of Johannesburg have found that high temperature heat-treatment at 200 degrees Celsius can halve this harmful mechanism in fly ash geopolymer concretes.

Written by Ms Therese van Wyk and Dr Abdolhossein Naghizadeh.

INTERVIEWS: For email interviews or questions, contact Dr Naghizadeh at anaghizadeh@uj.ac.za.

For interviews via mobile phone / Skype / Zoom with Dr Naghizadeh, contact Ms Therese van Wyk at Theresevw@uj.ac.za or +27 71 139 8407 (mobile) in Johannesburg, UTC + 2.

Dr Naghizadeh's doctoral research was partly funded by the Centre of Applied Research and Innovation in the Built Environment (CARINBE) at the University of Johannesburg.

How we might recharge an electric car as it drives

Engineers have demonstrated a practical way to use magnetism to transmit electricity wirelessly to recharge electric cars, robots or even drones
STANFORD SCHOOL OF ENGINEERING

Stanford engineers have taken a big step toward making it practical for electric cars to recharge as they speed along futuristic highways built to "refuel" vehicles wirelessly.

Although wireless charging pads already exist for smartphones, they only work if the phone is sitting still. For cars, that would be just as inconvenient as the current practice of plugging them in for an hour or two at charging stations.

Three years ago, Stanford electrical engineer Shanhui Fan and Sid Assawaworrarit, a graduate student in his lab, built the first system that could wirelessly recharge objects in motion. However, the technology was too inefficient to be useful outside the lab.

Now, in Nature Electronics, the two engineers demonstrate a technology that could one day be scaled up to power a car moving down the road. In the nearer term, the system could soon make it practical to wirelessly recharge robots as they move around in warehouses and on factory floors -- eliminating downtime and enabling robots to work almost around the clock.

"This is a significant step toward a practical and efficient system for wirelessly re-charging automobiles and robots, even when they are moving at high speeds," Fan said. "We would have to scale up the power to recharge a moving car, but I don't think that's a serious roadblock. For re-charging robots, we're already within the range of practical usefulness."

Wireless chargers transmit electricity by creating a magnetic field that oscillates at a frequency that creates a resonating vibration in magnetic coils on the receiving device. The problem is that the resonant frequency changes if the distance between the source and receiver changes by even a small amount.

In their first breakthrough three years ago, the researchers developed a wireless charger that could transmit electricity even as the distance to the receiver changes. They did this by incorporating an amplifier and feedback resistor that allowed the system to automatically adjusts its operating frequency as the distance between the charger and the moving object changed.

But that initial system wasn't efficient enough to be practical. The amplifier uses so much electricity internally to produce the required amplification effect that the system only transmitted 10% of the power flowing through the system.

In their new paper, the researchers show how to boosts the system's wireless-transmission efficiency to 92%. The key, Assawaworrarit explained, was to replace the original amplifier with a far more efficient "switch mode" amplifier. Such amplifiers aren't new but they are finicky and will only produce high-efficiency amplification under very precise conditions. It took years of tinkering, and additional theoretical work, to design a circuit configuration that worked.

The new lab prototype can wirelessly transmit 10 watts of electricity over a distance of two or three feet. Fan says there aren't any fundamental obstacles to scaling up a system to transmit the tens or hundreds of kilowatts that a car would need. He says the system is more than fast enough to re-supply a speeding automobile. The wireless transmission takes only a few milliseconds -- a tiny fraction of the time it would take a car moving at 70 miles an hour to cross a four-foot charging zone. The only limiting factor, Fan said, will be how fast the car's batteries can absorb all the power.

The wireless chargers shouldn't pose a health risk, said Assawaworrarit, because even ones that are powerful enough for cars would produce magnetic fields that are well within established safety guidelines. Indeed, the magnetic fields can transmit electricity through people without them feeling a thing.

Though it could be many years before wireless chargers become embedded in highways, the opportunities for robots and even aerial drones are more immediate. It's much less costly to embed chargers in floors or on rooftops than on long stretches of highway. Imagine a drone, says Fan, that could fly all day by swooping down occasionally and hovering around a roof for quick charges.

Who knows? Maybe drones really could be practical for delivering pizza.

###

This work is supported by a Vannevar Bush Faculty Fellowship from the U. S. Department of Defense.

Ultraviolet light exposes contagion spread from improper PPE use

Low-cost simulation technique can efficiently increase hospital workplace safety during COVID-19 pandemic

FLORIDA ATLANTIC UNIVERSITY

IMAGE: USING ULTRAVIOLET LIGHT, RESEARCHERS DISCOVERED THE PRESENCE OF FLUORESCENT SOLUTION ON THE HEALTH CARE WORKER'S SKIN, WHICH REPRESENTED AN EXPOSURE TO THE CONTAGION AND INDICATED THAT THEY MADE AN ERROR.CREDIT: RAMI A. AHMED, D.O.

Despite the use of personal protective equipment (PPE), reports show that many health care workers contracted the coronavirus disease (COVID-19), which raises substantial concerns about the effectiveness of the PPE. Highly sought after PPE used in hospitals and other health care settings is critical in ensuring the safety of those on the frontline of COVID-19, but only if they are used properly.

A physician from Florida Atlantic University's Schmidt College of Medicine and collaborators from the University of Arizona College of Medicine-Tucson and the Indiana University School of Medicine conducted a novel training technique to reinforce the importance of using proper procedures to put on and take off PPE when caring for patients during the pandemic. Researchers were able to vividly demonstrate how aerosol-generating procedures can lead to exposure of the contagion with improper use of PPE.

To detect contamination, Patrick G. Hughes, D.O., lead author, director of FAU's emergency medicine simulation program and an assistant professor of Integrated Medical Science, FAU's Schmidt College of Medicine, and collaborators, used a nontoxic fluorescent solution during a PPE training session for health care staff. They placed a highlighter refill in a warm water bath for 15 minutes to create a fluorescent solution, which is only visible under ultraviolet light.

For the experiment, published in the journal Medical Education, the researchers instructed health care staff to put on PPE, which included a cap, gown, surgical gloves, eye protection, face shield and N95 mask. In order to conserve vital PPE, supplies were wiped off and reused for multiple trainings. After health care staff in the study put on their PPE, they went in to a room to care for a simulated patient sprayed down with the invisible simulated contagion. In addition, the researchers added the fluorescent solution to a simulated albuterol nebulizer treatment, which was given to the mannequins during the scenario (not in a negative pressure room).

By turning off the lights, researchers were able to identify widespread simulated contagion on the PPE, both on the gloves and gowns from directly touching the simulated patient and on the face shields and masks from the aerosolized solution.


After completing the simulated case, the health care staff remained in their PPE and were taken to another room, where the lights were turned off prior to removing their PPE. Turning off the lights enabled the identification of widespread simulated contagion on the PPE, both on the gloves and gowns from directly touching the simulated patient and on the face shields and masks from the aerosolized solution. The researchers used a black light flashlight to examine each health care worker and to identify the presence of any fluorescent solution.

Following the flashlight examination, the health care staff completely removed their PPE. Researchers discovered the presence of fluorescent solution on the health care staff's skin, which represented an exposure to the contagion and indicated that they made an error while putting on or taking off their PPE.

Results from the experiment revealed that the most common error made by the health care staff was contaminating the face or forearms during PPE removal. In contrast, those who put on and took off their PPE according to guidelines had no signs of the fluorescent contagion on their skin or face.

Using ultraviolet light, researchers discovered the presence of fluorescent solution on the health care worker's skin, which represented an exposure to the contagion and indicated that they made an error while putting on or taking off their PP

"This training method allows educators and learners to easily visualize any contamination on themselves after they fully remove their personal protective equipment," said Hughes. "We can make immediate corrections to each individual's technique based on visual evidence of the exposure."

By providing health care staff with visual evidence of protection during patient encounters with high-risk aerosol-generating procedures, this innovative training method is helping to inspire trust in their training and PPE.

"This experiment demonstrated that following PPE training improves workplace safety and decreases the risk of transmission," said Hughes. "This simulation-based approach provides an efficient, low-cost solution that can be implemented in any hospital."

Hughes also conducted this training technique with FAU's emergency medicine resident physicians in the medical school's Clinical Skills Simulation Center, which uses high-tech and high-fidelity patient mannequins in life-like hospital and emergency room settings. The center applies sophisticated simulation and trainer technologies to educate medical students, resident physicians, registered nurses, first responders, certified nursing assistants, home health aides and community health care providers. The center has created models of hospital rooms, patient examination, and emergency rooms for simulated patient treatment. The rooms are fully equipped with hospital beds, gurneys or exam tables, monitors, IV poles, defibrillators, blood pressure cuffs, simulated oxygen ports, otoscopes and ophthalmoscopes and all equipment and supplies required to respond to medical and nursing interventions, including emergencies.

The simulation team uses high fidelity wireless, full body male and female mannequins. The simulators track all actions taken and all pharmacological agents given to the patients. If incorrect drugs or dosages are administered, the high-fidelity patient responds exactly as a human patient would respond. Preceptors and session facilitators provide guidance during the simulations.

###

Study co-authors are Kate E. Hughes, D.O., emergency medicine, University of Arizona College of Medicine -Tucson; and Rami A. Ahmed, D.O., emergency medicine, Indiana University School of Medicine, Indianapolis.

KRAKEN 

Fossil reveals evidence of 200-million-year-old 'squid' attack

UNIVERSITY OF PLYMOUTH

IMAGE: THE DRAMATIC COASTLINE NEAR CHARMOUTH IN DORSET, UK, HAS YIELDED A LARGE NUMBER OF IMPORTANT FOSSILS. view more 

CREDIT: LLOYD RUSSELL, UNIVERSITY OF PLYMOUTH

Scientists have discovered the world's oldest known example of a squid-like creature attacking its prey, in a fossil dating back almost 200 million years.

The fossil was found on the Jurassic coast of southern England in the 19th century and is currently housed within the collections of the British Geological Survey in Nottingham.

In a new analysis, researchers say it appears to show a creature - which they have identified as Clarkeiteuthis montefiorei - with a herring-like fish (Dorsetichthys bechei) in its jaws.

They say the position of the arms, alongside the body of the fish, suggests this is not a fortuitous quirk of fossilization but that it is recording an actual palaeobiological event.

They also believe it dates from the Sinemurian period (between 190 and 199 million years ago), which would predate any previously recorded similar sample by more than 10 million years.

The research was led by the University of Plymouth, in conjunction with the University of Kansas and Dorset-based company, The Forge Fossils.

It has been accepted for publication in Proceedings of the Geologists' Association and will also be presented as part of Sharing Geoscience Online, a virtual alternative to the traditional General Assembly held annually by the European Geosciences Union (EGU).

Professor Malcolm Hart, Emeritus Professor in Plymouth and the study's lead author, said: "Since the 19th century, the Blue Lias and Charmouth Mudstone formations of the Dorset coast have provided large numbers of important body fossils that inform our knowledge of coleoid palaeontology. In many of these mudstones, specimens of palaeobiological significance have been found, especially those with the arms and hooks with which the living animals caught their prey.

"This, however, is a most unusual if not extraordinary fossil as predation events are only very occasionally found in the geological record. It points to a particularly violent attack which ultimately appears to have caused the death, and subsequent preservation, of both animals."

In their analysis, the researchers say the fossilised remains indicate a brutal incident in which the head bones of the fish were apparently crushed by its attacker.

They also suggest two potential hypotheses for how the two animals ultimately came to be preserved together for eternity.

Firstly, they suggest that the fish was too large for its attacker or became stuck in its jaws so that the pair - already dead - settled to the seafloor where they were preserved.

Alternatively, the Clarkeiteuthis took its prey to the seafloor in a display of 'distraction sinking' to avoid the possibility of being attacked by another predator. However, in doing so it entered waters low in oxygen and suffocated.

Trump administration divided over new 5G network

AFP/File / SAUL LOEBThe Pentagon has expressed opposition to the deployment of a new 5G cellular network

The Trump administration is divided over the deployment of a new 5G cellular network, with the Pentagon, NASA and others at odds with other government agencies.

The five-member Federal Communications Commission (FCC) voted in late April to approve the deployment of a 5G cellular network by Ligado Networks.

Opponents of the plan argue that it would use spectrum that could potentially disrupt frequencies used for commercial and military Global Positioning System (GPS) signals.

The FCC decision has received the backing of Attorney General Bill Barr and Secretary of State Mike Pompeo.

But Pentagon chief Mark Esper, NASA, the Commerce Department, Department of Homeland Security and major airlines have voiced their opposition.

On Wednesday, top Pentagon officials pleaded their case before a Senate committee.

"There are too many unknowns, and the risks are too great to allow the proposed Ligado system to proceed in light of the operational impact to GPS," said Dana Deasy, the top advisor to the defense secretary for information technology.

Senator Jim Inhofe, a Republican from Oklahoma who chairs the Senate Armed Services Committee, also voiced his opposition to the project by Ligado, a Virginia company formerly known as LightSquared.

"I do not think it is a good idea to place at risk the GPS signals that enable our national and economic security for the benefit of one company and its investors," Inhofe said.

"After extensive testing and analysis, experts at almost every federal agency tell us that Ligado's plan will interfere with GPS systems," he said. "Interfering with GPS will hurt the entire American economy."

Inhofe said he had raised the question with President Donald Trump and that the FCC decision had been made "without cluing the president in on any of this."

Deasy said the Pentagon would lodge an appeal in a bid to have the FCC reverse its decision.

Defense top brass criticize Ligado's 5G proposal

Chief of Space Operations at US Space Force General John Raymond testifies before the Senate Armed Services Committee hearing on the Department of Defense Spectrum Policy and the Impact of the Federal Communications Commission's Ligado Decision on National Security during the COVID-19 coronavirus pandemic on Capitol Hill in Washington, DC Wednesday. Pool photo by Shawn Thew/UPI | License Photo

May 6 (UPI) -- Top Pentagon officials told lawmakers Wednesday that a proposed nationwide network to provide 5G and internet-of-things services was "too risky to be worth it."

"This is fundamentally a bad deal for America's national and economic security," said Dana Deasy, the Department of Defense's Chief Information Officer, at a Senate Armed Services Committee hearing on the recently-approved Ligado proposal and its implications for national security.


In April the Federal Communications Commission approved a proposal that would allow Ligado Networks to deploy technological services using the L-band spectrum that runs adjacent to the spectrum used for global positioning systems, which form the basis for most mapping software.

The Department of Defense has repeatedly criticized the proposal, saying it would disrupt defense operations as well as significant aspects of civilian life.

At Wednesday's hearing defense leaders warned that the Ligado plan would disrupt the accuracy of weapons systems, first responders' 911 navigation ability and shipping systems.

"GPS has also long been a critical technology that has supported the Nation's public safety, law enforcement medical and medical responders. It literally saves lives. While Americans at home are typically not under threat of purposeful electronic attack, the GPS services they depend on every day for life and livelihood are also threatened if the GPS signal and its environment are not protected from disruption," said General John W. Raymond, head of the newly-created United States Space Force.

Retired U.S. Coast Guard Admiral Thad W. Allen criticized the lack of transparency in the process by which the decision was made, as well as the likely technological consequences.

"In the case of Ligado Networks, FCC did not follow the normal regulatory process for reasons that remain unclear," Allen said, drawing a contrast from the process of issuing a license to Dish Networks to convert satellite service spectrum to terrestrial mobile broadband spectrum.

Ligado wrote a letter to the committee, which was read Wednesday, defending its technology as critical to 5G development.

"We now look forward to the opportunity to build a network that will advance our Nation's progress on the race to 5G," the company wrote.

Esper, lawmakers criticize FCC's approval of Ligado 5G proposal

Defense Secretary Mark Esper, shown here during an April 1 press conference, on Thursday tweeted criticism of an FCC-approved proposal to implement a national 5G and IoT network. Photo by Oliver Contreras/UPI | License Photo

April 23 (UPI) -- Secretary of Defense Mark Esper on Thursday criticized a proposal to deploy a nationwide network to provide 5G and internet-of-things services, saying it could disrupt GPS services millions of Americans rely on daily.

The FCC approved the proposal Monday, which would see Ligado Networks deploy 5G and internet-of-things services using L-band spectrum that runs adjacent to spectrum used for GPS.

"I applaud the congressional defense leaders for their efforts to protect national security, ensure economic prosperity, promote technological leadership, & preserve Americans' way of life," Esper wrote on Twitter.

Esper also posted a link to a Wednesday statement from the Senate Armed Services Committee criticizing the proposal.

MONOPOLY CAPITALISM

RELATED Federal agencies urge FCC to ban China-owned telecom over security risks

"The problem here is that Ligado's planned usage is not in the prime mid-band spectrum being considered for 5G -- and it will have a significant risk of interference with GPS reception, according to the National Telecommunications and Information Administration," said the statement, which was signed by leadership from both SASC and the House Armed Services Committee, from both political parties.

"The signals interference Ligado's plan would create could cost taxpayers and consumers billions of dollars and require the replacement of current GPS equipment just as we are trying to get our economy back on its feet quickly -- and the FCC has just allowed this to happen," the members of Congress said.

Thursday's statement is not the first time the Pentagon has criticized the Ligado proposal, and lawmakers tried to stop the proposal earlier in April.

WAIT A MINUTE WHAT DO THEY KNOW WE DON'T

RELATED DoD extends travel restrictions for troops, families through June 30

The DoD is also not alone among federal departments in its criticism.

Over the weekend, the Pentagon issued a joint statement with the Department of Transportation saying the disruption to the Global Positioning System -- which is the basis for most mobile mapping software -- would be massively disruptive to civilian and military life.

"Americans rely on our Global Positioning System each day for many things: to locate citizens in need of emergency assistance through our E-911 system, to secure our financial system, to order and receive shipments, to travel by car for work and leisure, to facilitate commercial trucking and construction work, and even to make a simple cellphone call," the statement said

"Our Departments rely on GPS each day for all those reasons as well to coordinate tactical national security operations, launch spacecraft, track threats, and facilitate travel by air and sea. The proposed Ligado decision by the Federal Communications Commission will put all these uses of GPS at risk."

                                            

PROVING MONOPOLY CAPITALISM IS THE AMERICAN WAY

Pompeo has no evidence about virus lab leak: China 

POOL/AFP/File / Andrew HarnikUS Secretary of State Mike Pompeo has said that there was 'enormous evidence' that the new coronavirus came out of a Wuhan lab

China hit back Wednesday at US Secretary of State Mike Pompeo over his claims that the coronavirus originated in a laboratory in Wuhan, saying he "doesn't have any" evidence.

Washington and Beijing have clashed repeatedly over the virus, which emerged in China late last year but has since spiralled into a global pandemic.

Theories that the virus came from a maximum-security virology lab in Wuhan have swirled since earlier this year, but were brought into the mainstream last month by US government officials.

Pompeo said on Sunday that there was "enormous evidence" to show that the new coronavirus originated in a Chinese lab.

"I think this matter should be handed to scientists and medical professionals, and not politicians who lie for their own domestic political ends," said foreign ministry spokeswoman Hua Chunying.

"Mr Pompeo repeatedly spoke up but he cannot present any evidence. How can he? Because he doesn't have any."

On Wednesday, Pompeo reiterated his claims, though with a caveat.

"We don't have certainty, and there is significant evidence that this came from the laboratory -- those statements can both be true," Pompeo told reporters.

Most scientists believe the new virus jumped from animals to humans, with suspicion focused on a market in Wuhan that sold wildlife for meat.

US President Donald Trump has been increasingly critical of China's management of the outbreak, saying last week he had seen evidence linking the virus to the Wuhan lab and threatening new trade tariffs against Beijing.

The United States is the worst-hit country in the world, with more than 70,000 deaths.

Beijing has accused the US of trying to divert attention from its domestic handling of the outbreak.

"We urge the US to stop... shifting the focus to China," Hua said.

"It should handle its domestic affairs properly first. The most important thing now is to control the US' domestic pandemic spread and think of ways to save lives."

- Virus tensions -

The World Health Organization has said US claims about the origin of the virus were "speculative".

The top US epidemiologist Anthony Fauci has echoed the WHO's statement, telling National Geographic that all evidence so far "strongly indicates" a natural origin.

But countries including the United States and Australia have called for an investigation into how the disease transformed into a global pandemic.

The WHO has also said it was waiting for an invitation from China to participate in its investigations into the animal origins of the virus.

But Beijing's UN ambassador in Geneva said Wednesday that China will not invite international experts to investigate the source of COVID-19 until after securing the "final victory" over the virus.

The envoy, Chen Xu, also said China has to counter the "absurd and ridiculous" US politicisation of the new coronavirus, adding that the "right atmosphere" was needed for an invitation to take place.

Officially, China's toll for the virus is 4,633 -- but several countries have cast doubt on whether the numbers are accurate.

China and the US had only recently soothed economic tensions, with the signing of a "phase one" trade deal in January.

But since then the world's two biggest economies have been exchanging insults and accusations.

Trump and his administration angered Beijing by repeatedly referring to "the Chinese virus" when discussing the COVID-19 outbreak.

A foreign ministry spokesman in Beijing later suggested it may have been the US military which brought the virus to Wuhan, and China has sought to distance itself from the virus.

Hua said on Wednesday that there had been "many reports" suggesting that there were coronavirus cases discovered in the US or France last year, and said that this suggests the "sources (of the virus) are very diverse."

bye-rox-lth-bfm/bgs

 RIP
Florian Schneider, co-founder of Germany's iconic Kraftwerk, dead at 73

AFP/File / BRUNO FERRANDEZKraftwerk, shown here in 2005, crafted the blueprint for genres from new wave to synth-pop, hip hop to rock, industrial to techno

Kraftwerk's Florian Schneider, co-founder of the pioneering electronic music group that re-wired the future of pop, has died, the group's management said Wednesday. He was 73 years old.

Schneider died following a short battle with cancer, according to a statement citing his fellow co-founder Ralf Huetter, obtained by AFP from Kraftwerk's publicist in Los Angeles.

Schneider and Huetter began their artistic collaboration in 1968 as part of the so-called "krautrock" movement -- a broad experimental genre blending psychedelic rock with electronic rhythms and early synthesizers, seen as a rebellion against the Anglo-Saxon pop brought in by British and American troops.

But Kraftwerk, launched in 1970, hatched a far more singular vision from their "Kling Klang" studio in the western German city of Duesseldorf.

Their influence on par with The Beatles, the duo crafted the blueprint for genres from new wave to synth-pop, hip hop to rock, industrial to techno.

The nearly 23-minute title track of their 1974 album "Autobahn" -- the German word for highway -- comprised the entire first side of the LP with a prototypical, hypnotizing sound of the future, punctuated with car horns, doors slamming and ignition.

The industrial clang, sparse arrangements and computerized beats of Kraftwerk -- which means "power station" in German -- brought international recognition to the group who famously said they wanted to make music more as machines than as men.

Schneider's tools included the electric flute, violin, electric guitar and synthesizer. He also sang with Huetter, who played keyboards.

Their haunting basslines, synthesizer pads and drum machines combined with robotic vocals captured the attention of a dizzying array of stars past and present, including David Bowie, Madonna, Daft Punk and Kanye West.

AFP/File / John MACDOUGALLFlorian Schneider left Kraftwerk in 2008 but the rest of the band he co-founded continues to tour

"My favorite group is a German band called Kraftwerk -- it plays noise music to 'increase productivity,'" Bowie told Playboy in 1976, when asked what will happen to music's future.

"Sound as texture, rather than sound as music. Producing noise records seems pretty logical to me," Bowie told the magazine.

The late legend named his largely instrumental track "V-2 Schneider" off the classic 1977 album "Heroes" after the Kraftwerk co-founder.

- Never-ending 'Autobahn' -

AFP/File / ROBERT ATANASOVSKIKraftwerk's 22-minute title track of their 1974 album "Autobahn" -- the German word for highway -- comprised the entire first side of the LP with a prototypical, hypnotizing sound of the future, punctuated with car horns, doors slamming and ignition

Born April 7, 1947, Schneider was the son of Paul Schneider-Esleben a prominent architect whose designs included the Cologne airport.

The musician met Huetter when the pair were both students in Duesseldorf, where they began cultivating their pioneering concepts, tapping into the ubiquity of machines and the growing place of technology in daily life.

While "Autobahn" was perhaps their best-known album internationally, they also found global success with "Radioactivity" (1975), "Trans-Europe Express" (1977), "The Man Machine" (1978) and even the later "Tour de France Soundtracks" (2003).

The notoriously enigmatic group in 2018 also took the Grammy for Best Dance/Electronic Album for "3-D The Catalogue," a high-tech recreation of their back albums.

They won a 2014 lifetime achievement Grammy but the six-time Rock and Roll Hall of Fame nominees have yet to be chosen for induction into that pantheon of music royalty.

Schneider's "innovative music left a lasting legacy and his work will continue to exert influence across various genres for years to come," said the Recording Academy in a statement.

"Florian's creativity knew no bounds," the body behind the Grammys said, adding "our culture is richer" thanks to the German artist.

Schneider left the group at the end of 2008 and did not participate in future tours.

Before the coronavirus pandemic halted shows worldwide, the group in February had announced a North American tour of its immersive "3-D Concerts" -- a concept launched in 2013 that fuses three-dimensional visuals and performance art with Kraftwerk's music catalog.

AFP/File / ROBERT ATANASOVSKIKraftwerk, shown here in 2005, captured the attention of a dizzying array of stars past and present, including David Bowie, Madonna, Daft Punk and Kanye West

Music world tributes poured out to Schneider upon news of his death, including from the "Father of Disco" Giorgio Moroder of Italy, another major electronic dance music mastermind, who called the Kraftwerk co-founder "one of my heroes."

"The mighty Florian Schneider has left this earth. 2020 is really just the worst thus far," tweeted rockers Garbage, as Russian DJ Nina Kravitz wrote "what would electronic music be without Kraftwerk?"

France's legendary Jean-Michel Jarre also hailed Schneider: "My dear Florian Your Autobahn will never end."