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Localized Surface Plasmon Resonance - an overview | ScienceDirect Topics

 https://t.co/mzS7vVSREJ
https://t.co/353PdAX2fa
https://t.co/3yBImjOdd4
In some cases, almost 100% of the light energy can be converted to the second harmonic frequency. These cases typically involve intense pulsed laser beams passing through large crystals, and careful alignment to obtain phase matching.
In other cases, like second-harmonic imaging microscopy, only a tiny fraction of the light energy is converted to the second harmonic—but this light can nevertheless be detected with the help of optical filters.
Generating the second harmonic, often called frequency doubling, is also a process in radio communication; it was developed early in the 20th century, and has been used with frequencies in the megahertz range. It is a special case of frequency multiplication.
An electron (purple) is being pushed side-to-side by a sinusoidally-oscillating force, i.e. the light's electric field. But because the electron is in an anharmonic potential energy environment (black curve), the electron motion is not sinusoidal.
The three arrows show the Fourier series of the motion: The blue arrow corresponds to ordinary (linear) susceptibility, the green arrow corresponds to second-harmonic generation, and the red arrow corresponds to optical rectification.
Electro-optic rectification (EOR), also referred to as optical rectification, is a non-linear optical process that consists of the generation of a quasi-DC polarization in a non-linear medium at the passage of an intense optical beam.
For typical intensities, optical rectification is a second-order phenomenon[1] which is based on the inverse process of the electro-optic effect.
It was reported for the first time in 1962,[2] when radiation from a ruby laser was transmitted through potassium dihydrogen phosphate (KDP) and potassium dideuterium phosphate (KDdP) crystals.
https://t.co/Px03xrubJ0

The term "electro-optic" is often erroneously used as a synonym for "optoelectronic".
Opto-electronics (or optronics) is the study and application of electronic devices and systems that source, detect and control light, usually considered a sub-field of photonics.
In this context, light often includes invisible forms of radiation such as gamma rays, X-rays, ultraviolet and infrared, in addition to visible light.
Optoelectronic devices

are electrical-to-optical

or optical-to-electrical transducers,

or instruments that use such devices in their operation.
Optoelectronics is based on the quantum mechanical effects of light on electronic materials, especially semiconductors, sometimes in the presence of electric fields.
•Photoelectric or photovoltaic effect, used in:
◦photodiodes (including solar cells)
◦phototransistors
◦photomultipliers
◦optoisolators
◦integrated optical circuit (IOC) elements
•Photoconductivity, used in:
◦photoresistors
◦photoconductive camera tubes
◦charge-coupled imaging devices
•Stimulated emission, used in:
◦injection laser diodes
◦quantum cascade lasers
•Lossev effect, or radiative recombination, used in:
◦light-emitting diodes or LED
◦OLEDs
•Photoemissivity, used in
◦photoemissive camera tube
Important applications of optoelectronics include:
•Optocoupler
•Optical fiber communications
An opto-isolator (also called an optocoupler, photocoupler, or optical isolator) is an electronic component that transfers electrical signals between two isolated circuits by using light.
https://t.co/ku83nBU7Ck

An opto-isolator contains a source (emitter) of light, almost always a near infrared light-emitting diode (LED), that converts electrical input signal into light, a closed optical channel (also called dielectrical channel),
and a photosensor, which detects incoming light and either generates electric energy directly, or modulates electric current flowing from an external power supply.
The sensor can be a photoresistor, a photodiode, a phototransistor, a silicon-controlled rectifier (SCR) or a triac. Since LEDs can sense light in addition to emitting it, construction of symmetrical, bidirectional opto-isolators is possible.
An optocoupled solid-state relay contains a photodiode opto-isolator which drives a power switch, usually a complementary pair of MOSFETs.
A slotted optical switch contains a source of light and a sensor, but its optical channel is open, allowing modulation of light by external objects obstructing the path of light or reflecting light into the sensor.
Electronic equipment and signal and power transmission lines can be subjected to voltage surges induced by lightning, electrostatic discharge, radio frequency transmissions,

switching pulses (spikes) and perturbations in power supply.
Transformers and opto-isolators are the only two classes of electronic devices that offer reinforced protection — they protect both the equipment and the human user operating this equipment.
They contain a single physical isolation barrier, but provide protection equivalent to double isolation.

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NotTheMacAnon
NotTheMacAnon
@NotTheMacAnon1
2020 marks the start of the quantum dot revolution.

Completely ignoring the fact that "photocatalytic generation of reactive oxygen species (ROS) from quantum dots (QDs) has been widely reported."

Results: It was found that whereas singlet oxygen (1O2) was not produced by photoexcited QDs, superoxide anion(O2− )and hydroxyl radicals(OH) were generated by QDs, especially in the presence of a physiological concentration of electron donating agent including NADH.

Using cell metabolic activity assays and various probes of ROS generation, the formation of ROS in cellular environments was demonstrated.

Conclusion: Illumination of QD-treated cells and bacteria with light did affect viability. The above results, together with those of assays in the presence of various scavengers of specific ROS, indicate that the formation of ROS by QDs mainly proceeded via electron transfer.
FOR LATER READ
NotTheMacAnon
NotTheMacAnon
@NotTheMacAnon1
In continuum mechanics, stress is a physical quantity that expresses the internal forces that neighbouring particles of a continuous material exert on each other, while strain is the measure of the deformation of the material.

For example, when a solid vertical bar is supporting an overhead weight, each particle in the bar pushes on the particles immediately below it. When a liquid is in a closed container under pressure, each particle gets pushed against by all the surrounding particles.

The container walls and the pressure-inducing surface (such as a piston) push against them in (Newtonian) reaction.

These macroscopic forces are actually the net result of a very large number of intermolecular forces and collisions between the particles in those molecules. Stress is frequently represented by a lowercase Greek letter sigma (σ).

Residual stresses inside a plastic protractor are revealed by the polarized light.
TECH
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NotTheMacAnon
NotTheMacAnon
@NotTheMacAnon1
During a normal pregnancy, oxidative stress enhances antioxidant mechanisms that are capable of reacting by way of enzyme activity and non-enzyme free radical deactivators. However, pregnancy is also a state in which this adaptation and balance may be easily disrupted.

There is strong evidence that a chronicin flammatory reaction combined with the presence of a local oxidizing environment may play a vital role in the etiology and development of complications during pregnancy.

In late pregnancy, damage to DNA (especially when it is caused by oxidative stress) is associated with pre-eclampsia(PE), intrauterine growth restriction (IUGR), and the death of mothers in developing countries; it largely determines pregnancy – related susceptibility to diseases

The referential values of ROS and NOS and their minimal and safe concentrations or physiologically beneficial concentrations are yet to be determined.

The measurement of oxidative stress in vivo is perceived as controversial,

as the sen-sitivity and specificity of various oxidative stress markers is unknown.. .
HEALTH
NotTheMacAnon
NotTheMacAnon
@NotTheMacAnon1
Did the paedophiles create the virus?

I think so!

Is Joe Biden the paedophiles choice?

Jury’s out.

Scumbags

Lock them all up and f their vaccine.
BIDEN
NotTheMacAnon
NotTheMacAnon
@NotTheMacAnon1
Transduction is the process by which foreign DNA is introduced into a cell by a virus or viral vector.

Viral vectors are tools commonly used by molecular biologists to deliver genetic material into cells.

Viruses have evolved?

specialized molecular mechanisms

to efficiently

transport their genomes

inside the cells they infect.

Delivery of genes, or other genetic material, by a vector is termed transduction and the infected cells are described as transduced.

A transducer is a device that converts energy from one form to another. Usually a transducer converts a signal in one form of energy to a signal in another.
HEALTH

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Dark II Light
@SheLuvsTGA
From a truther friend 🙏
💥👇💥 Thread 💥👇💥
Now at last some good News!

Thanks Rob Osborne - From the scientists mouth. Officially its the flu.From natural news .com
“I have a PhD in virology and immunology. I'm a clinical lab scientist and have tested 1500 "supposed" positive
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Shrey Srivastava
Shrey Srivastava
@BlogShrey
#DDDD $LBPS $LOAC

A thread on the potential near term catalysts behind why I have increased my position in 4d Pharma @4dpharmaplc (LON: #DDDD):


1) NASDAQ listing. This is the most obvious.

The idea behind this is that the huge pool of capital and institutional interest in the NASDAQ will enable a higher per-share valuation for #DDDD than was achievable in the UK.

Comparators to @4dpharmaplc #DDDD (market capitalisation £150m) on the NASDAQ and their market capitalisation:

Seres Therapeutics: $2.33bn = £1.72bn (has had a successful phase 3 C. difficile trial); from my previous research (below) the chance of #DDDD achieving this at least once is at least


Kaleido Biosciences: $347m = £256m. 4 products under consideration, compared to #DDDD's potential 16. When you view @4dpharmaplc's 1000+ patents and AI-driven MicroRx platform (not to mention their end-to-end manufacturing capability), 4d's undervaluation is clear.
SCIENCE
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10-K Diver
10-K Diver
@10kdiver
1/

Get a cup of coffee.

In this thread, we'll cover *State Quantities* and *Flow Quantities*.

This mental model can help us analyze many different entities -- from complex engineering systems to publicly traded companies.


2/

A "State Quantity" is something that's associated with a *specific point in time*.

For example, the number of followers a Twitter account has is a state quantity. This number can go up and down over time. But at any one *specific* time point, it's fixed.

3/

Similarly, the amount of cash a company has is a state quantity.

This cash balance can also rise and fall over time.

But pick any one *specific* time point -- and the company can only have one *specific* cash balance at that time point.

4/

By contrast, a "Flow Quantity" is something that's associated with a time *interval* rather than a time *point*.

For example, the number of followers gained by a Twitter account is a flow quantity. It's meaningful only when we specify a time interval (eg, the last 30 days).

5/

A simple analogy is that a State Quantity is like a photo -- a snapshot at a particular *point* in time.

But a Flow Quantity is like a video -- a record of events that take place during a particular time *interval*.
SCIENCE , FINANCE
Duncan J Campbell
Duncan J Campbell
@Maven1967
What is going on at SWANSEA UNIVERSITY in Wales?
1.
https://t.co/d5NKtNlxxa
Sounds as if its connected to Bill Gates "LUCIFERASE" Vaccine?

2.
https://t.co/k0w1mjaPg0

"HILLARY RODHAM CLINTON SCHOOL OF LAW"
- AT SWANSEA UNIVERSITY!!!


3.
https://t.co/jifuWq6cGq
Remember all those FIRES, over the Summer!!!

4.
https://t.co/H3lstFyYx8
WUHAN PARTNERSHIP

"Links between Swansea & Wuhan date back to 1855 when Swansea missionary Griffith John founded the Wuhan Union Hospital.
This relationship was strengthened when representatives of the two cities signed an agreement".


5.
https://t.co/5b1JqiEQzi
Swansea University Strengthens Links with China
SCIENCE
Mark Tomasovic
Mark Tomasovic
@MarkTomasovic
What is carbon capture? And how does it work?

While carbon capture is regularly discussed in the media, no one really ever explains what it is.

Below is a quick thread discussing the technology behind traditional carbon capture 👇

Carbon capture is broadly the "capture" of CO2 emissions from a power plant or other type of industrial facility.

Technology is connected to the "tailpipes" of these facilities and is used to remove CO2 from the plant exhaust.

Once the CO2 is removed from the plant exhaust, it is typically pressurized and sent under ground for permanent storage.

This step is called "sequestration" and is why experts often talks about "carbon capture and sequestration" or "CCS".

So how do you "capture" the CO2 molecules from exhaust?

Currently, one of the most economic forms of carbon capture is called "amine-based" capture.

An "amine" is a special liquid chemical which selectively grabs on to CO2 molecules.

To get the amine to grab on to the CO2, the amine is put into the top of a large column, while the exhaust is put into the bottom of the column.

The exhaust bubbles up through the column, and the amine drips down.

The liquid amine and gas exhaust mix in the column.
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👇 Thread. New deck getting published this week: "Consumer startups are awesome, and here's what I'm looking to invest in at Andreessen Horowitz." If you want to read it, subscribe to my newsletter here: https://t.co/262t8eh0wf


1/ A lot of new consumer technologies have been introduced to US households in the last 100 years. But it's taken many of them - like the telephone - more than 50 years to get to the majority of the US. Why is that?


2/ We had to literally teach people how to use phone. Which end goes to your mouth, which goes to your ear. Say "hello" when people call. The motivation of consumers to talk to their friends has always been there, but we had to teach the behavior


3/ If you compare phones to the latest technologies, there's been a huge shift. Things are being picked up much faster.


4/ Even while there's been all this innovation recently, physically speaking, we are still the same human beings from 100,000 years ago.
STARTUPS
Nikita Poojary
Nikita Poojary
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Time for a Thread🧵On yesterday’s “F&O Pe Charcha - Diary Of An Option Seller” with @Mitesh_Engr by @Paytm Money

Why Gain/loss ratio is important that the batting average
• More than the Win Loss ratio check the total Gain /loss ratio
• If your avg loss is 1% and avg gain is +5% then even if you are losing in 7 positions and winning in 3 out of 10 still you will be net profitable

Treat Trading as a business:
• Stick to a single strategy. Eg: A restaurateur usually wouldn’t be changing his recipe on a daily basis
• Mitesh Sir only works on BO or BD strategy, as he is a versatile trader

• Any trader should atleast experience 3 scenarios i.e. bull, bear & consolidation
• Target 4% per month i.e. 48% p.a.
• Option buying requires skill, everyday there wont be huge momentum, so buying options won’t yield good results, but high chances of falling into a bad habit

Stock Selection:
• In F&O segment there are ~150 stocks
• Not everyday all stocks will move
• Only 5-7 stocks move upside or downside
• Focus only these momentum stocks
• Check which one is moving
• Range BO/BD never disappoints. BO/BD from a rectangle (consolidation)
MPLEARNINGS , ALL , OPTION SELLING
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Kieran Snyder
Kieran Snyder
@KieranSnyder
1 There's a chasm between an NLP technology that works well in the research lab and something that works for applications that real people use. This was eye-opening when I started my career, and every time I talk to an NLP engineer at @textio, it continues to strike me even now.

2 Research conditions are theoretical and/or idealized. A huge problem for so-called NLP or AI startups with highly credentialed academic founders is that they bring limited knowledge of what it takes to build real products outside the lab.

3 A product is ultimately a thing that people pay for - not just cool technology or user experience. But I’m not even talking about knowledge gaps in go-to-market work. I'm talking purely technical gaps: how you go from science project to performant + delightful user experience.

4 Most commoditized NLP packages solve well-understood problems in standard ways that sacrifice either precision or performance. In a research lab, this is not usually a hard trade-off; in general, no one is using what you make, so performance is less important than precision.

5 In software, when you’re making something for real people to use, these tradeoffs are a big deal. Especially if you’re asking those people to pay for what you’ve made (can’t get away from that pesky GTM thinking). They expect quality, which includes precision AND performance.
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The Troll Zoo
The Troll Zoo
@TrollZoo
1. This is "Hollie The Card".

She's a Doctor, Physician, PhD, MA, Clinical Psychologist, Hospital Consultant, PTSD consultant, Long Covid Consultant.

(Thread)


2. Although sometimes she’s also an AUTHOR and English Academic.


3. A Hospital Consultant and ex Gymnast.

(Pinterest public profile)


4. A Physician, Doctor, or hospital consultant.

A “Hospital Consultant”, would probably mean a senior doctor, in the UK at least.


5. Hollie changes her Twitter picture and bio so often, it’s hard to keep up with her qualifications.
TWITTER
Lindsey Simmons
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@LynzforCongress
Joshua Hawley, Missouri's Junior Senator, is an autocrat in waiting.

His arrogance and ambition prohibit any allegiance to morality or character.

Thus far, his plan to seize the presidency has fallen into place.

An explanation in photographs.

🧵

Joshua grew up in the next town over from mine, in Lexington, Missouri. A a teenager he wrote a column for the local paper, where he perfected his political condescension.

2/


By the time he reached high-school, however, he attended an elite private high-school 60 miles away in Kansas City.

This is a piece of his history he works to erase as he builds up his counterfeit image as a rural farm boy from a small town who grew up farming.

3/


After graduating from Rockhurst High School, he attended Stanford University where he wrote for the Stanford Review--a libertarian publication founded by Peter Thiel..

4/

(Full Link: https://t.co/zixs1HazLk)


Hawley's writing during his early 20s reveals that he wished for the curriculum at Stanford and other "liberal institutions" to change and to incorporate more conservative moral values.

This led him to create the "Freedom Forum."

5/
HISTORY