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- Создано: 13-01-22
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tungsten-moly.com
Описание: tungsten-moly.com Molybdenum metal is usually produced by powder metallurgy techniques in which Mo powder is hydrostratically compacted and sintered at about 2100°C. Hot working is done in the 870-1260°C range. Moly forms a volatile oxide when heated in air above about 600°C and therefore high temperature applications are limited to non-oxidizing or vacuum environments. Molybdenum Alloys have excellent strength and mechanical stability at high temperatures (up to 1900°C). Their high ductility and toughness provide a greater tolerance for imperfections and brittle fracture than ceramics. The unique properties of molybdenum alloys are utilised in many applications: High temperature heating elements, radiation shields, extrusions, forging dies, etc; Rotating X-ray anodes used in clinical diagnostics; Glass melting furnace electrodes and components that are resistant to molten glass; Sprayed coatings on automotive piston rings and machine components to reduce friction and improve wear. For specialised applications, Mo is alloyed with many other metals like Lanthanated Molybdenum Alloy: Mo-tungsten alloys are noted for exceptional resistance to molten zinc; Mo is clad with copper to provide low expansion and high conductivity electronic circuit boards; Mo-25% rhenium alloys are used for rocket engine components and liquid metal heat exchangers which must be ductile at room temperature. Except for Molybdenum, Tungsten is also a popular metal. Tungsten is an invaluable element in the alloying process, where elements are blended to form new and improved metals known as alloys. Tungsten provides a unique contribution, as it imbues exceptional strength, corrosion resistance, and other useful properties to base metals. Besides being a great alloying element, tungsten can also be the base for its own alloys. Tungsten alloy Tungsten alloys, sometimes referred to as heavy alloys, are usually 90-97% tungsten with the rest of its composition being a matrix of metals which improve the ductility and machinability of the resulting alloy. There is no true naming standard for these alloys, as they are set individually by the manufacturer and are not superimposable onto a general scheme such as with the alloys of steel or aluminum. Tungsten nickel iron alloys The most common of the tungsten alloys, tungsten nickel iron alloys are top of the list in terms of ductility, strength, and density. They are a silvery-grey color, have a range of densities from 16.85-19.3 g/cm3, and are also known as Densalloy?, Mallory, WNiFe, and/or Densimet?. These metals have tensile strengths ranging from 600-1000 MPa, which surpasses most if not all other alloys. These alloys have good machining qualities and plasticity and can withstand intense temperatures, while still having a thermal conductivity that is 5 times that of die & punch steels. They have 1.7 times the radiation shielding capabilities of lead and are non-toxic to biological systems (which cannot be said for lead). Iron makes these alloys magnetic, which is important to know if they are planned to be used in any magnetism-sensitive operations such as medical imaging equipment. Tungsten nickel iron alloys have a low expansion coefficient useful for glass-to-metal seals and possess high moduli of elasticity, which makes them resistant to elastic deformation. These alloys are perfect for radiation shielding, as its high density matched with its radiation resistance are ideal for protective components. Some notable applications include balance weights, security and defense applications, ballasts, bearing assemblies, and more. Tungsten nickel copper alloys The non-magnetic cousin to tungsten nickel iron alloys is the tungsten nickel copper alloys. They are about as popular as nickel-iron alloys, but generally, have lower tensile strength (500-700 MPa) and ductility. They are great electrical conductors and are easy to machine despite their high mechanical strength. They possess excellent thermal stability and can shield from radiation about as well as other tungsten alloys. The greatest advantage to tungsten nickel copper alloys is their non-magnetic nature; this feature allows them to be used in applications where tungsten nickel iron alloys would be magnetically disruptive. They are widely specified in oncology tools, electrical sensor shields, guidance system components, and military technology. In addition, there are other kinds of Tungsten alloys like Tungsten Heavy Alloy and Copper Tungsten Alloy are more and more popular. And in the industrial production, other metals like Tantalum, Titanium, Niobium and Chromium are all applied more and more often.
Дата Публикации: 13-01-22
tpmach.com
Описание: tpmach.com In recent years, food safety issue has arouse wide public attention. Air pollution and application of pesticides leave pollutant and toxic residue on fruits and vegetables. They are covered by heavy metal elements, chemical components, dust and mites. Traditional cleaning can only clear away a part of hazardous substance, which is far from thorough cleaning. Fruit Vegetable Washing Mahcine is mainly used in washing fruits or vegetables, it is an essential equipment on the fruit and vegetable juice processing line. Fruit washer machine is also widely used in the processing of varied fruit products. To ensure the quality of fruit products or fruit juice, clean fruit is very important, so the washing of fruit is essential. Fruit Vegetable Washer can remove the pesticide residue on them. The machine is designed to solve this problem, and it aims to clean fruit thoroughly and remove the pesticide residue. They can liberate you from heavy cleaning work, as well as satisfy your demand for clean and healthy fruit. In terms of fruit juice production, qualified fruit washing machine is a guarantee for wholesome fruit juice. The washer machine is also a surf washing machine, which is one type of fruit and vegetable washing machine. It consists of water tank, blower, upender, blower, roller, spray water tube, hopper, etc. The blower blows the air out and keeps the water spinning, so the water flows quickly, scours the surface of the fruit and washes the dirt. The machine adopts air stirring and does not destroy the integrity of the fruit. After cleaning the fruits, they are sent to the elevator. In order to avoid secondary pollution and get more sanitary fruits, the dirt and sand of the washing materials are sent to the receptive tank at the bottom of the fruit washing machine. Besides, when producing the fruits or vegetables, another equipment called Fruit Vegetable Cutting Machine is worth to mention as well. Fruit Vegetable Cutting Machine is currently the most advanced machine in China specialized for slicing vegetables and fruits. The vegetable slicer machine has wide applications. It can cut potato, cucumber, apple and other vegetables and fruits into the round or diagonal slice. The number, diameter, and angle of the feeding inlet could be customized. There is no restriction on the thickness of the vegetables or fruits. The machine is mainly composed of frame, the feed inlet, rotating cutter head, motor, and transmission part. Put the material into the feed inlet, then the high speed rotating cutter will cut the material into slices. Attention: 1. It's strictly forbidden to put metal objects or tools into the feed inlet of the fruit slicer machine. 2. The vegetables or fruits to be cut should be washed beforehand. Clay or sand is not allowed to be attached to avoid damaging the cutter. 3. It's strictly forbidden to put your hands into the feed inlet of the industrial fruit slicer while feeding the raw materials. 4. The switch must not be splashed while cleaning the machine. 5. Check and change the v-belt in case the commercial vegetable slicer runs powerlessly. For the fruits and vegetable processing industry, there are many Fruit and Vegetable Processing Machinery needed during the process. Beside the machine mentioned above, others like Fruit and Vegetable Peeling Machine, Fruit Vegetable Juice Machine, Fruit and Vegetable Sorting Machine, etc. Also, with the improving of the living standard, food producing industry like cake and snake become more and more popular nowadays, so the equipments such as Food Snack Machine, Dough Snack Processing Machine, Cake Processing Machine and Snack Food Processing Machine are commonly seen.
Дата Публикации: 13-01-22
tosterfood.com
Описание: tosterfood.com Oats are among the healthiest grains on earth. They're a gluten-free whole grain and a great source of important vitamins, minerals, fiber and antioxidants. Studies show that oats and oatmeal have many health benefits. These include weight loss, lower blood sugar levels and a reduced risk of heart disease. Oats are a whole-grain food, known scientifically as Avena sativa. Oat groats, the most intact and whole form of oats, take a long time to cook. For this reason, most people prefer rolled, crushed or steel-cut oats. Instant (quick) oats are the most highly processed variety. While they take the shortest time to cook, the texture may be mushy. Oats are commonly eaten for breakfast as oatmeal, which is made by boiling oats in water or milk. Oatmeal is often referred to as porridge. They're also often included in muffins, granola bars, cookies and other baked goods. The nutrient composition of oats is well-balanced. They are a good source of carbs and fiber, including the powerful fiber beta-glucan. They also contain more protein and fat than most grains. Oats are loaded with important vitamins, minerals and antioxidant plant compounds. This means that oats are among the most nutrient-dense foods you can eat. Whole oats are high in antioxidants and beneficial plant compounds called polyphenols. Most notable is a unique group of antioxidants called avenanthramides, which are almost solely found in oats. Avenanthramides may help lower blood pressure levels by increasing the production of nitric oxide. This gas molecule helps dilate blood vessels and leads to better blood flow. In addition, avenanthramides have anti-inflammatory and anti-itching effects. Ferulic acid is also found in large amounts in oats. This is another antioxidant. Oats contain large amounts of beta-glucan, a type of soluble fiber. Beta-glucan partially dissolves in water and forms a thick, gel-like solution in the gut. The health benefits of beta-glucan fiber include reducing LDL and total cholesterol levels, reducing blood sugar and insulin response and increasing feeling of fullness and the growth of good bacteria in the digestive tract. When you shop for oats, you'll see several types on the store shelves. They're all based on "oat groats", which are the whole oat kernel. Instant oats: Oat groats that have been steamed and flaked. Rolled oats(also called regular or old-fashioned oats): Oat groats that have been steamed and rolled into flakes that are thicker (and thus take longer to cook) than instant oats. Steel-cut oats (also called Irish oats): You get the whole oat kernel, cut up. These take about 20 minutes to cook. Scottish oats : These are like steel-cut oats, but instead of being cut, they are ground. Oat groats: This is the whole oat kernel - no cuts, flakes, or grinding. They take longer to cook than other oats. Give them 50-60 minutes to cook, after you bring the water to a boil. You can cook oatmeal on your stove top, in your microwave, or in a slow cooker. "Overnight Oats" are also popular. These are oats that are soaked overnight in a liquid like milk or yogurt. Also, they can be made into many different types of food like Fruit Oatmeal, Chia Seed Oatmeal, Yogurt Oatmeal, Nuts Oatmea and so on. They are also a great combination with Grain Cheerios, Corn Flakes and Grain Balls.
Дата Публикации: 13-01-22
5 Things to Know About Portable Power Stations
Описание: 5 Things to Know About Portable Power Stations These pricey battery-powered devices are the only type of generator that can be used indoors safely Since generators emit carbon monoxide, they require that you take critical safety measures, including running the device outside, at least 20 feet away from any structure. But in an age when we can charge our smartphones with a battery pack that fits inside a pants pocket, shouldn't there be a simpler way to restore power in the wake of a storm? Or, say, power a campsite without the constant hum of a gas-fueled generator? Such is the promise of portable power stations, also known as battery-powered inverter generators. Essentially, they're oversized rechargeable batteries—about the size of a countertop microwave oven—that you plug into a typical 110-volt outlet to top off. When duty calls, you can safely run a portable power station inside, since it doesn't generate any emissions. They have enough capacity to power a few small appliances for a short time. With a host of different outlets (standard 120v outlets, USB ports, and DC chargers), you can use the station to charge electronics, too. And the units often come with portable solar panels, to add more charging capabilities and extend runtime. “These generators have no fumes and all of the models we tested made virtually no noise,” says test engineer Dave Trezza, who oversees generator testing at Consumer Reports. “But, if these power stations go dead and you’re unable to use your solar panels, you can’t recharge them. You can’t just use another gallon of gas.” We see models from brands, including Goal Zero, Humless, K2, and Kohler in our portable power station ratings. Some companies, like Goal Zero, market these portable power stations as perfect for apartment preparedness during storms (as opposed to single-family homes with a yard that can accommodate a generator). How We Test Portable Power Stations In our labs, CR test engineers evaluate five key measures to rate portable outdoor power stations: runtime, power delivery, power quality, ease of use, and noise. To test runtime, we run a constant 300-watt load to simulate powering a TV and a few lights. We also hook each battery up to a side-by-side refrigerator to see how long it lasts. The best model in our tests powered the fridge for 44 hours on one charge (the worst only managed for 13 hours). For power delivery, or how well a model can maintain voltage when tasked with different loads, we use a variety of devices, including a 1?2-horsepower submersible pump and a 10,000-BTU air conditioners. We also judge noise output and found that, as a category, these batteries run quietly: All the models we tested earned an Excellent score for noise. Below, our experts share some pros and cons on using portable power stations. See how the most popular models fared in our ratings, and check our generator buying guide to compare portable power stations to other types of generators. 1. They Can’t Deliver Nearly as Much Power as Gas Generators As with their gasoline-fueled counterparts, portable power stations require a transfer switch should you wish to power bank things such as your furnace, overhead lights, or any thing else in your home that’s hardwired. But while a recreational inverter generator would probably keep the TV and a few lights on for 8 to 13 hours on one tank of gas, you'd see anywhere from 3 to 9 hours of power, under the same circumstances, with a portable power station. And you won't be able to run, for instance, your power-guzzling well pump. 2. They Take Awhile to Charge In our tests, most of these models require hours of charging (typically overnight) to provide you with a full battery and max runtime. So—assuming you fully charged the battery before a predicted weather event—a portable power beauty device station could give you hours of electricity to run a refrigerator or another essential appliance. But Trezza notes that once the battery is dead, if you’re without power and minimal sun, there’s no way to recharge. 3. Charging With Solar Panels Can Be Iffy and Lengthy If you're dealing with an outage or you're otherwise off the grid, charging the power station via solar panels is your only option—and that's provided you have good sun and no obstructions. In our tests, we found that the solar panels can add to the runtime, but that might only amount to an extra hour or two of power with larger appliances. 4. They’re Not All That Portable Portable power stations are about the size of an average microwave oven, but they're fairly heavy—most in our tests weigh more than 80 pounds. That means you'll likely need an extra pair of hands to lift one into the trunk of your car. Some of the models come with wheels, but not all wheels are large in size, which makes rolling them across a lawn difficult. 5. They Don’t Come Cheap The portable power stations we tested cost between $1,500 and $3,500. And our best portable gas generator costs less than the worst portable power station. Before buying one of these power stations, consider if you might be better served by a portable generator. In the event of a outage, you can continue to add fuel, and portable generators typically provide enough power to keep larger appliances running. Check out our buying guide on generators to learn which type might best suit your needs. Generator Tips Damaging storms can happen at any time. On the 'Consumer 101' TV show, host Jack Rico learns from Consumer Reports’ expert, Paul Hope, how to avoid being left in the dark during a power outage.
Дата Публикации: 13-01-22
How Do Touch Screens Work on Laptops and Tablets?
Описание: How Do Touch Screens Work on Laptops and Tablets? Tapping into touch screens Most of us are pretty familiar with touch screens. We use this technology daily with our phones, computers, at the ATM, or at the grocery store checkout. Even restaurants have implemented touch display ordering and payment right at the table. Even though we’re constantly tapping and swiping our screens all day long, few of us can actually answer the question: how do touch screens work? We’re here to help uncover the mystery behind these interactive screens. Together, we can finally dispel the rumor that touch screens are operated by miniature robot elves completing your pointer finger’s many commands. Let’s discuss the most common touch screen technologies, how you can differentiate them, how they work, and how these technologies have impacted our daily lives. Capacitive vs resistive touch screens With the first touch screen debuting in 1965, we’ve seen incredible advancements in touch screen technology and computing technology in general. If we told E.A. Johnson that over 2 billion people currently carry touch screens in their pockets every day, he probably wouldn’t have believed us. But that same technology he developed for the Royal Radar Establishment helped shape the future of the modern touch screen technology that we use daily . There are many iterations of touch screen technology including infrared and surface acoustic wave (SAW), but there are two that most of us are familiar with. The most common smart touch board screens we interact with today are capacitive and resistive touch screens. Let’s get to know how these technologies work, and where you’ll see each. Capacitive touch screens Capacitive touch screen technology is the style we interact with most. This is the kind of display we see in our smartphones, laptops, and tablet screens, and digital signage. Capacitive screens are made up of multiple layers of glass and plastic, coated with a conductor material like indium tin oxide or copper. This conductive material responds when contacted by another electrical conductor, like your bare finger. When you touch your screen, an electric circuit is completed at the point where your finger makes contact, changing the electrical charge at this location. Your device registers this information as a “touch event.” Once a touch event has been registered, the screen’s receptors signal this event to the operating system, prompting a response from your device. This is the application’s interface that you experience. Capacitive touch screens generally have a brighter, clearer appearance and are much more sensitive than resistive touch smart board screens. We tend to see capacitive touch screens in more modern technologies like smartphones and tablets. They give us the ability to experience high-quality imagery that imitates reality. With social media so integrated into our lives, we’re constantly sharing and experiencing life through our devices. Being able to interact with high-quality applications with ease is made possible with the latest capacitive touch screens. Resistive touch screens Resistive touch screens work exactly how their name implies - with resistance to touch. A glass or hard plastic layer is blanketed by a resistive metallic layer that conducts charge. The two are separated by spacers in the screen so that when your finger presses firmly on the plastic protective layer, the two layers make contact changing the electric charge at that location, which cues the software to respond. Resistive screens are not as bright as capacitive because of their thick blue and yellow colored layers that make their interface appear darker than capacitive screens. You’ll often see resistive screens used on ATM machines, checkout stands, and POS (point of sale) terminals. They tend to be much more durable and affordable than capacitive screens, thanks to that hard plastic outer layer. Each screen has strengths and weaknesses that make it a better choice for certain applications. Capacitive screens with portable monitor offer more flexibility in functionality as resistive screens lack the ability to register multiple touch points at the same time. Think about when you zoom in on your smartphone - you’re using two fingers at different receptors to zoom in on an image. Resistive touch screens get confused when you try to apply multiple points to them, since their technology relies on recognizing pressure at a specific location. What touch screens detect What touch displays detect differs depending on if the screen is capacitive or resistive. Resistive screens rely on applied pressure which means that sometimes the tip of a pen or another object can initiate a response from the system. Capacitive touch screens use electrical conductors rather than pressure to recognize a command and respond. But have you ever wondered why capacitive touch screens seem to only work with skin? While that’s not entirely the case, capacitive screens do depend on a specific amount of electrical charge to get a response from the operating system. This means that other objects with the same charge as your bare finger could complete the same request when using your phone, tablet, or interactive touch screen laptop. This is why touch screens respond to styluses, special gloves, and the occasional pocket-dial. Before you slip on a pair of gloves ready to text all of your friends about how awesome your new gloves are though, you may want to make sure you’ve got the right pair. Touch screen gloves use conductive thread in the fingertips to maintain the natural electric charge of your finger. This means that not just any glove will be able to register your touch, so make sure you get the right kind of gloves before braving the winter with your smartphone. While conductive threads and styluses work with touch displays, other objects like a regular pen will not. The difference is in the electric charge of the object. Pens actually have too much electrical charge for a touch screen to recognize. Your screen depends on the perfect recipe of electric charge to complete your requests. Fascinating, isn’t it? Screen protectors If touch screens work based on their ability to conduct and receive energy, how do touch screen protectors work? Capacitive touch screens detect electrical current so they don’t need to experience the pressure of your finger like resistive screens do. If your screen protector uses electrically transparent material, it won’t affect the functionality of your screen because it will still be able to register the change in electric charge. The good news is that as technology in touch screens has advanced, so have their durability. Touch TV Screen protectors aren’t as necessary now as they were when consumers were first introduced to touch screen products. Many of us are still scarred by the first time we shattered the glass display on our shiny new device. Contrary to over-protective techies, you don’t need to worry so much about the safety of your screen thanks to developments in materials. Most devices use scratch-resistant material like Gorilla? Glass to protect your screen if it takes a short tumble - though we do not recommend testing your screen’s limits. It’s a durable glass, not the Incredible Hulk. For those who may be coordination-challenged, screen protectors are still a good option to keep your screen in pristine condition. Most screen protectors are either made of plastic or tempered glass. Plastic protectors help to protect from scratching but don’t do much for impact. If you’re one of those coordination-challenged individuals we mentioned earlier, you may want to consider leveling up to a tempered glass protector, and maybe even a sturdy case to go along with it. Depending on the thickness of the plastic, you may feel a difference in the sensitivity of your touch screen. Tempered glass adds a thick layer to your screen as well, but the feel is closer to your device’s original screen.
Дата Публикации: 13-01-22
The Wire Harness Manufacturing Process: A Guide for Electronics Engineers
Описание: The Wire Harness Manufacturing Process: A Guide for Electronics Engineers Coaching children’s recreational league basketball when my kids were growing up was very rewarding—even if it was more like herding cats than playing actual basketball. There is one thing that stands out in my mind, however, and that was when a play worked the way we designed it. We first diagramed the play out for the kids, and then we practiced it until they understood the moves. When it finally came together in a game, it was a beautiful thing to see. Today, as I work with wire harnesses that are built for electronic devices, I am reminded of those days coaching the kids on how to put the play together. First, the wire harness specifications are drawn up in the same way we would diagram the play. Then, the harness is meticulously laid out, just as we demonstrated to the kids how to execute the play. There’s a lot more to the process of course, and thankfully, the wire harnesses usually don’t talk back to us. Here are more details of the PCB wiring harness manufacturing process that your contract manufacturer should go through when building your assemblies. Input: What Your CM Needs for the Wire Harness Manufacturing Process Contract manufacturers often build both flat ribbon cable assemblies and wire harnesses. To distinguish between the two, a multicore cable assembly is an external connection to devices and will have different environmental considerations, such as their thickness, insulation type, and flexibility. A wire harness, on the other hand, will provide the connectivity between systems in an electromechanical assembly, such as connecting a power supply to a motherboard. Wire harnesses are laid out and built on a panel that has pegs positioned strategically where the wires will branch out into different directions, or connectors need to be added. This way, the harness is laid out to the exact dimensions that are required. Usually, you specify these dimensions, and contract manufacturers are used to getting a wide range of information to work with. The information can be something as simple as a hand-drawn note, or a series of complex 3D CAD models, as well as everything in between. However, as with anything that is manufactured, the more detailed documentation and precise specifications you can provide, the fewer problems there will be on the assembly floor. Here is a sampling of the data that will best help your contract manufacturer when building your wire harness: Detailed connectors images that show pin locations. Wire lists that specify wire colors, nets, and connector pin-outs. Bill of materials with part numbers. Full assembly drawing with label locations, assembly instructions and tolerances. Finished harness test specifications. Key Points of the Manufacturing Process to Build Your Wire Harness With the documentation in hand, you should expect your contract manufacturer to follow a general process in building your wire cable harness assembly: Design review: First off, your CM will examine your bill of materials and other documentation to make sure that everything they need is in place. They will also evaluate your specified parts to see if those are the best choices due to cost, availability, and performance. If not, they will search for available replacements. Materials preparation: Once the bill of materials is finalized, the CM will next purchase the components and materials needed for production and test of the harness. Assembly documentation: At the same time as procurement, the CM will be creating assembly documentation for the manufacturing floor based on your input. This will include detailed assembly steps, images and illustrations, and test procedures. Additionally, the assembly panel will be created with all the necessary pegs set at the specified locations. Wire harness production: Now, the harness will be built. The assembly technicians will cut the PVC insulated wires to length, and lay it out on the assembly panel according to the build instructions. Connectors will be added, bundles of wires will be tied together, and labels will be attached. QA: Once completed, the wire harness will go through the testing that has been prepared for it to check continuity. The harness will also be checked for construction and labeling, and tested for fit if the system that it is intended for is on-site. The building of your wire harness is a pretty straightforward operation, but there are some details you should be aware of to help to speed the assembly through manufacturing. The Dos and Don’ts of Having Your Wire Harness Built The component manufacturer usually provides termination recommendations for how the high temperature wires should be attached. Be sure, then, to use those recommendations—such as stripped and bare or stripped and tinned—as that is what the component is built for. The same goes for torque values on fasteners, in which you should also use the manufacturer’s recommended values. You should also provide generic specifications for wires, such as 300V or 600V, instead of a specific UL code. This gives the CM the flexibility to use what works best for the harness requirements that is also readily available and cost the least. Specific UL-coded wire may not be essential for the harness and instead could turn out to be difficult to find or expensive to use.
Дата Публикации: 13-01-22
5 Things to Consider When You Install a SATA Hard Drive
Описание: 5 Things to Consider When You Install a SATA Hard Drive Before you install a SATA hard drive, be sure you have the right cables and slots available on your motherboard. Here's what you need to know. Ready to upgrade your hard drive and found you're dealing with a SATA connector? SATA drives are easy to set up, support hot swapping, and the interface is reasonably fast. We'll show you everything you need to know about installing a SATA drive, and how to connect the power and data cable. What Are SATA Drives Serial ATA (SATA) connectors remain a common interface between the drive and the motherboard. The image above shows a 2.5" SATA hard drive from Fujitsu with the data port on the left and the power port on the right. On older SATA drives, you might also see a 4-pin Molex power connector. You'll find SATA interfaces in both hard drisk drives (HDDs) and solid state drives (SSDs). SATA drives were introduced to replace IDE and Enhanced IDE (Parallel ATA) drives. SATA removes the master-slave relationship between parallel hard drives, with each drive connecting to the motherboard using its own SATA adapter. As well as a specific port, SATA offers substantial improvements in data transfer rates. The original SATA specification transfers data at speeds up to 150 MB/s. The latest revision, SATA 3.5, transfers data at speeds up to 1,969 MB/s (1.969 GB/s), enables active drive temperature monitoring, and better integrates with industry I/O standards. While the latest SATA iteration isn't in use for consumer drives, the technology does eventually filter into those products. Should You Get a SATA or PCI Express SSD? Solid State Drives sales have rapidly increased throughout the past few years, from around 39 million units in 2012 to an estimated 360 million in 2021. With SSDs, you can choose between two types of connectors: SATA and PCI Express (PCIe). Wondering which one is right for you? And do you need an SSD at all? Consider your use case: If you need a large amount of storage at an affordable price and don't plan on using it as an everyday drive running your operating system, i.e. it doesn't need to be ultra-fast, then a regular HDD drive is the right choice. In that case, you'll want a connection compatible with your motherboard, most likely SATA connector. If you're looking for the fastest possible drive and neither price nor storage capacity are an issue, consider an SSD and check whether your computer has a PCIe slot. Note that SATA SSDs are only available in the smaller 2.5" form factor. In addition to non-ultrabook laptops, that also makes them ideal as external drives. 1. Hard Drive Installation Safety Guidelines Before installing a new hard drive, take the following precautions to prevent damaging your hardware. Turn the Power Off Before you open the case and begin fiddling with the hardware, shut your system down. Then turn off the mains power switch. You'll find the switch at the back of your case. Once turned off, hold the power button down for a few seconds to discharge any remaining power. Ground Yoursel Electrostatic shock can wreck your drive as soon as you take it out of its packaging. An electrostatic shock comes from a static energy build-up in your body. As you touch the metallic case of the drive, you transfer that energy, which can then fry vital components. Luckily, most new hardware arrives in an anti-static bag and should come with a handling warning, too. Moreover, some modern components have integrated anti-shock technology that should prevent hardware damage from an unexpected static shock. But just because your drive has shock protection, it doesn't mean you shouldn't be wary of affecting other hardware components. The easiest way to protect your hardware is to ground yourself. Touch a metal table leg or the case of your computer (do this after discharging your motherboard, as described above). Alternatively, buy an anti-static wristband. 2. SATA DATA and Power Connectors This article assumes you have a modern motherboard that no longer has IDE connectors. IDE drives haven't featured in consumer computers for some time. The overwhelming majority of computers and motherboards sold in recent years will focus solely on SATA drives (with a few exceptions, of course). Let's familiarize ourselves with the SATA 7P connector and port. The left connector is for data (typically a red cable), while the second powers your drive. It is possible to buy an all-in-one, 22-pin SATA 15P cable that combines both connectors (but is less flexible). 3. SATA Data and Power Cables Your new HDD or SSD probably arrived with at least its interface cable (the red cable in our example images above and below). But your drive also needs power. That power usually comes in the form of a 4-pin Molex power connector with a SATA drive specific connector. A SATA HDD can arrive with a range of input connectors, allowing you to choose between a SATA power connector (the empty port to the left of the red interface cable, below) or 4-pin Molex connector (the cable on the far right, below). You can choose either one but not both at the same time! A reader notes that you should "never use the Molex (4-pin) to SATA power adapter" because "most hard drives and solid state drives require the orange 3.3V wire to board to supply power for the drive electronics." This may cause the drives to fail at spinning up or registering in the computer's BIOS, Device Manager, or Disk Management. Thank you for the heads-up, Doc! Consequently, some modern HDDs have done away with 4-pin Molex power inputs and now offer just a SATA power input. A SATA SSD will arrive with only a SATA power connector and a data transmission cable.
Дата Публикации: 13-01-22
Insecticide - chemical substance
Описание: Insecticide - chemical substance insecticide, any toxic substance that is used to kill insects. Such substances are used primarily to control pests that infest cultivated plants or to eliminate disease-carrying insects in specific areas. Insecticides can be classified in any of several ways, on the basis of their chemistry, their toxicological action, or their mode of penetration. In the latter scheme, they are classified according to whether they take effect upon ingestion (stomach poisons), inhalation (fumigants), or upon penetration of the body covering (contact poisons). Most synthetic insecticides penetrate by all three of these pathways, however, and hence are better distinguished from each other by their basic chemistry. Besides the synthetics, some organic compounds occurring naturally in plants are useful insecticides, as are some inorganic compounds; some of these are permitted in organic farming applications. Most insecticides are sprayed or dusted onto plants and other surfaces traversed or fed upon by insects. Modes of penetration Stomach poisons are toxic only if ingested through the mouth and are most useful against those insects that have biting or chewing mouth parts, such as caterpillars, beetles, and grasshoppers. The chief stomach poisons are the arsenicals—e.g., Paris green (copper acetoarsenite), lead arsenate, and calcium arsenate; and the fluorine compounds, among them sodium fluoride and cryolite. They are applied as sprays or dusts onto the leaves and stems of plants eaten by the target insects. Stomach poisons have gradually been replaced by synthetic insecticides, which are less dangerous to humans and other mammals. Contact poisons penetrate the skin of the pest and are used against those arthropods, such as aphids, that pierce the surface of a plant and suck out the juices. The contact insecticides can be divided into two main groups: naturally occurring compounds and synthetic organic ones. The naturally occurring contact insecticides include nicotine, developed from tobacco; pyrethrum, obtained from flowers of Chrysanthemum cinerariaefolium and Tanacetum coccineum; rotenone, from the roots of Derris species and related plants; and oils, from petroleum. Though these compounds were originally derived mainly from plant extracts, the toxic agents of some of them (e.g., pyrethrins) have been synthesized. Natural insecticides are usually short-lived on plants and cannot provide protection against prolonged invasions. Except for pyrethrum, they have largely been replaced by newer synthetic organic insecticides as technical products. Fumigants are toxic compounds that enter the respiratory system of the insect through its spiracles, or breathing openings. They include such chemicals as hydrogen cyanide, naphthalene, nicotine, and methyl bromide and are used mainly for killing insect pests of stored products or for fumigating nursery stock. Synthetic insecticides The synthetic contact insecticides are now the primary agents of insect control. In general they penetrate insects readily and are toxic to a wide range of species. The main synthetic groups are the chlorinated hydrocarbons, organic phosphates (organophosphates), and carbamates. Chlorinated hydrocarbons The chlorinated hydrocarbons were developed beginning in the 1940s after the discovery (1939) of the insecticidal properties of DDT. Other examples of this series are BHC, lindane, Chlorobenzilate, methoxychlor, and the cyclodienes (which include aldrin, dieldrin, chlordane, heptachlor, and endrin). Some of these compounds are quite stable and have a long residual action; they are, therefore, particularly valuable where protection is required for long periods. Their toxic action is not fully understood, but they are known to disrupt the nervous system. A number of these insecticides have been banned for their deleterious effects on the environment. Organophosphates The organophosphates are now the largest and most versatile class of insecticides. Two widely used compounds in this class are parathion and malathion; others are Diazinon, naled, methyl parathion, and dichlorvos. They are especially effective against sucking insects such as aphids and mites, which feed on plant juices. The chemicals’ absorption into the plant is achieved either by spraying the leaves or by applying solutions impregnated with the chemicals to the soil, so that intake occurs through the roots. The organophosphates usually have little residual action and are important, therefore, where residual tolerances limit the choice of insecticides as soil disinfectant. They are generally much more toxic than the chlorinated hydrocarbons. Organophosphates kill insects by inhibiting the enzyme cholinesterase, which is essential in the functioning of the nervous system. Carbamates The carbamates are a group of insecticides that includes such compounds as carbamyl, methomyl, and carbofuran. They are rapidly detoxified and eliminated from animal tissues. Their toxicity is thought to arise from a mechanism somewhat similar to that for the organophosphates. Environmental contamination and resistance The advent of synthetic insecticides in the mid-20th century made the control of insects and other arthropod pests much more effective, and such chemicals remain essential in modern agriculture despite their environmental drawbacks. By preventing crop losses, raising the quality of produce, and lowering the cost of farming, modern insecticides and fungicide increased crop yields by as much as 50 percent in some regions of the world in the period 1945–65. They have also been important in improving the health of both humans and domestic animals; malaria, yellow fever, and typhus, among other infectious diseases, have been greatly reduced in many areas of the world through their use. But the use of insecticides has also resulted in several serious problems, chief among them environmental contamination and the development of resistance in pest species. Because insecticides are poisonous compounds, they may adversely affect other organisms besides harmful insects. The accumulation of some insecticides in the environment can in fact pose a serious threat to both wildlife and humans. Many insecticides as formulation products are short-lived or are metabolized by the animals that ingest them, but some are persistent, and when applied in large amounts they pervade the environment. When an insecticide is applied, much of it reaches the soil, and groundwater can become contaminated from direct application or runoff from treated areas. The main soil contaminants are the chlorinated hydrocarbons such as DDT, aldrin, dieldrin, heptachlor, and BHC. Owing to repeated sprayings, these chemicals can accumulate in soils in surprisingly large amounts (10–112 kilograms per hectare ), and their effect on wildlife is greatly increased as they become associated with food chains. The stability of DDT and its relatives leads to their accumulation in the bodily tissues of insects that constitute the diet of other animals higher up the food chain, with toxic effects on the latter. Birds of prey such as eagles, hawks, and falcons are usually most severely affected, and serious declines in their populations have been traced to the effects of DDT and its relatives. Consequently, the use of such chemicals began to be restricted in the 1960s and banned outright in the 1970s in many countries.
Дата Публикации: 13-01-22
weihuagrpcrane.com
Описание: weihuagrpcrane.com Cranes are different from other pieces of construction equipment because at their most basic function, they do not require other machinery or power to function. The bulldozer, excavator or tractor required some form of power – whether it be steam or gas, or oil. Many modern construction equipment dates back to some time in the 1900s. A crane is a machine that is used to lift and move heavy loads, machines, materials, and goods for a variety of purposes. They are used in all different sectors of industry, from construction to manufacturing to shipbuilding and material loading. Cranes are common along skylines as they are necessary to build the skyscrapers we so often see in our cities today. And cranes can be debided into different types such as Overhead Crane, Gantry Crane& and Port Crane. While there are many different types of cranes, there are a few basic components or Crane Accessories like Hoist and Trolley worth mentioning. The main parts that can be found on a crane are as follows. The Boom The boom is the most recognizable part of a crane. The boom is a long arm that can either be telescopic or fixed. They take on a variety of roles depending on the type of crane and how it is built. They are able to work without jibs and are sometimes the main component on a crane. The primary purpose of the boom is to lift, move and position material. They bear the majority of the load and are responsible for determining the reach of the crane. The Jib The jib crane is the lattice-type structure attached to the end of the boom. Using a lattice-type build helps to reduce the weight it adds to the front of the boom. It is fixed in length and cannot be extended or retracted like a boom can. Some versions of mobile cranes have a jib fixed to the end of the boom to help move and lift materials. The jib or jib arm has one main purpose: to help keep the material clear of the main support so that it doesn't hit it while being moved. That being said, jibs are not always required and are often looked at as extra pieces that can be used when needed. The Rotex Gear The Rotex gear is the mechanism below the cab of the crane. It allows the cab and boom to rotate left and right. A simple movement, but incredibly important for the function of the machine. Counterweights The name "counterweight" pretty much describes the purpose of them: to counter the weight on the front of the crane while lifting material to prevent tipping. They help add stability to the machine and generally increase stability. Many cranes have adjustable counterweights so that they fit the specific requirements of a load or job. On tower cranes, for example, the counterweight can be seen at the other end of the jib. Outriggers Outriggers may be one of the most important factors for crane safety. The function of an outrigger is to supply additional support. The purpose of an outrigger is to distribute the load of the crane over a large enough area so that the crane itself doesn’t tip over or become unstable. All outriggers should either meet or exceed the weight requirements of a crane or job. Outriggers do not compensate for unstable land. OSHA requires cranes to be assembled on firm ground that is drained and graded sufficiently. Supporting outriggers are meant to be used in conjunction with proper ground standards and do not make up for unstable ground. Reinforced-Steel Cable In order for cranes to actually lift and move material, they require some kind of line or rope to do the actual lifting. In the case of cranes, this material is a reinforced steel cable. Steel ropes were first used for mining hoists in the 1830s. The wires used today are highly reinforced, resistant to corrosion, absorb any movement or force, and have extremely high breaking points. The Hook Finally, the crane must have some way for materials to be attached to it. The most typical way this is done is through a hook. The lifting hook on cranes is usually equipped with a safety latch to prevent the material from slipping off the hook in transit. Crane lifting hooks are often made of steel or wrought iron. Hooks for heavy-duty cranes and loads are usually heat-treated and forged in order to make the hook as strong as possible.
Дата Публикации: 13-01-22