Duke - TDD-Global

Q thin film advantage and disadvantage

Duke Release Time: June 24, 2024, 3:52 PM

The minimum thickness of a thin film is not universally defined, as it greatly depends on the application and material properties. Generally, thin films are considered to be a few nanometers (nm) to several micrometers (µm) in thickness. For optical applications, such as anti-reflective coatings, films can be as thin as a quarter of the wavelength of the light they interact with, which often falls into the range of 100-200 nm. In electronics, particularly in semiconductor manufacturing, films can range from a few nm for layers like gate oxides to several µm for features like interconnects. The critical factor is that the film must be thin enough to exhibit different physical or chemical properties compared to the bulk material, providing the desired functionality.

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Q during mitosis and meiosis kinetochore fibers are thought to

WilliamPeacock

Duke Release Time: June 19, 2024, 4:37 AM

Phloem fibers, found in the bast of various plants, have diverse applications due to their durability and strength. Flax, hemp, jute, and kenaf are key players in this category. Flax is renowned for its high quality and is commonly utilized in linen goods because of its strong yet not very elastic nature, making it ideal for clothing. Hemp boasts excellent strength and adaptability to different environments, making it a popular choice for fibers and composites. Jute is highly biodegradable and primarily used in the production of rope and hemp products. Among lesser known varieties, red hemp shows promise in paper manufacturing and nonwoven items due to its fast growth rate and top-notch fiber quality. Each type of fiber possesses distinct qualities that cater to specific industry requirements, from fashion to automotive uses, underscoring the vital role of resilient fibers in sustainable material development.

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Q how to keep yarn pom poms from falling apart

SuzanneGracie

Duke Release Time: June 1, 2024, 5:52 PM

Macrame, a form of textile produced using knotting techniques, can be beautifully done with yarn, adding a cozy, textured look to your creations. To start, select a yarn of your choice; wool or cotton yarns are ideal due to their durability and ease of handling. Cut the yarn into lengths according to your project size. Secure your yarn to a dowel or rod to create a stable base. Begin with basic knots; the Lark’s Head knot to attach your yarn, then progress to Square knots and Spiral knots for pattern creation. Remember, tension is key in macrame, so keep your knots tight and consistent. As you grow more confident, experiment with various colors and thicknesses of yarn, and incorporate beads or rings for added texture. Practice will perfect your technique, leading to unique and personalized macrame pieces.

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Q how to iron polypropylene fabric

EgbertHudson

Duke Release Time: June 1, 2024, 2:40 PM

Ironing polypropylene fabric requires caution due to its low melting point. Always use a pressing cloth to act as a barrier between the iron and the fabric. Set the iron to its lowest heat setting, and avoid direct contact by not pressing down too hard. Instead, lightly glide the iron over the pressing cloth. Test this method on a small, inconspicuous area of the fabric first to ensure there’s no damage. If possible, steam can be a safer alternative, as it avoids direct contact, reducing the risk of melting. Always check the fabric’s care label for specific instructions, as some polypropylene materials can’t withstand heat at all.

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Q how to fix a pipe

DeirdrePitman

Duke Release Time: May 6, 2024, 6:28 AM

To make a peace pipe, also known as a calumet, it’s important to approach the task with respect for its cultural significance, primarily among Native American tribes. Traditionally, the bowl is crafted from a soft stone like catlinite or pipestone, and the stem from a hollowed-out wooden stick. First, obtain a piece of pipestone, shaping it into a bowl using files and sandpaper for smoothness. Drill a hole in the center for the tobacco and a channel on the side to attach the stem. For the stem, select a straight piece of wood, hollow it out carefully, and shape it to your desired length and design. Finally, fit the stem into the bowl’s channel securely. Decoration varies by culture, so if you choose to add personal touches, strive to do so with mindfulness of its origins and meaning.

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Q what is pvc in kubernetes

MortimerPollitt

Duke Release Time: April 28, 2024, 6:22 AM

In Kubernetes, PVC stands for Persistent Volume Claim. It is a request for storage by a user. PVCs let users abstract the details of how the storage is provided and how it’s consumed. When a user needs storage, they simply create a PVC specifying size, access modes (like read/write), and sometimes performance requirements. An administrator sets up PVs (Persistent Volumes) that back these claims, and the Kubernetes control plane matches PVCs with appropriate PVs. This mechanism decouples the specific details of storage (like whether it’s SSD or HDD, NFS, or a cloud provider’s storage solution) from the needs of the pods, allowing for a more flexible and portable way to manage storage resources in a Kubernetes cluster.

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Q how to tell which pigment is which on a chromatograph

EmmaSheridan

Duke Release Time: April 23, 2024, 6:50 AM

To determine which pigment is which on a chromatograph, compare the chromatogram to known standards. Each pigment has a characteristic Rf value (the ratio of the distance moved by the pigment to the distance moved by the solvent). Measure these distances for your sample, and then compare them to documented Rf values for known pigments under similar conditions (solvent, paper type, etc.). It’s crucial to ensure that the experimental conditions are consistent with those of the standards for accurate identification. Additionally, pigments can often be visually distinguished based on their color. For example, chlorophyll typically appears green, while carotenoids appear orange or yellow. Combining Rf values with visual analysis provides a reliable method for pigment identification.

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Q how long do polyester strings last

BridgetFinn

Duke Release Time: April 22, 2024, 3:28 AM

Polyester strings, widely favored in the tennis community for their durability and ability to sustain high levels of play, typically last around 15 to 20 hours of active gameplay before notable performance degradation occurs. The key factor attributing to their longevity is the material’s inherent resistance to tension loss, which maintains the string’s playability over time. However, this duration can fluctuate based on a player’s intensity, frequency of play, and hitting style. While durable, polyester strings lose their elasticity and can become stiff, leading to a decrease in comfort and an increased risk of injury over time. Therefore, regular players are advised to restring their rackets periodically to maintain optimal performance and reduce the risk of injury.

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Q does polyester shrink when dry cleaned

RoseOwen

Duke Release Time: April 19, 2024, 1:19 AM

Polyester, a synthetic fiber known for its durability and resistance to shrinking and stretching, has a mixed reputation regarding snagging. It is less prone to snagging compared to natural fibers like cotton or wool due to its smooth and resilient texture. However, the susceptibility to snags can vary depending on the weave or knit of the fabric and the quality of the polyester. Finely woven or knitted polyester fabrics can snag if caught on sharp objects or rough surfaces. To minimize snagging, it’s advisable to handle polyester garments with care and avoid contact with sharp edges. Regular maintenance and following the garment’s care instructions can also help in preserving the fabric’s appearance and preventing snags.

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Q how to measure bike tyres

OscarDick

Duke Release Time: July 1, 2024, 12:24 PM

Identifying a cracked engine block requires keen observation. Symptoms include visible cracks on the block’s surface, unexplained coolant loss, engine overheating, white smoke from the exhaust, or oil and coolant mix, leading to a milky hue in the oil. Additionally, poor engine performance or failure to start can be indicators. To accurately diagnose, inspect the engine block for visible signs of damage, check for fluid leaks, and monitor the engine’s temperature and performance closely. For a definitive identification, consider a pressure test or seeking a professional mechanic’s evaluation. These methods help in accurately determining the presence and severity of a crack, crucial for deciding on repair or replacement.

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GeraldineJohn Release Time: February 26, 2024, 6:24 PM

To balance tires at home. using a portable tire balancer is a helpful solution. Here are the necessary tools: a portable tire balancer. an upright jack. a car jack. a tire wrench. a flat tire. and lead wheel weights. First. locate a flat and level area for the balancer to sit on. The garage floor is suitable as the balancer utilizes gravity to find the point on the tire. With the vehicle lifted onto jack stands using a car jack. remove one wheel at a time with the tire wrench. While removing the wheels. check for any foreign objects that could cause imbalance and remove them if present. Proceed by mounting each wheel onto the portable balancer according to its instructions and start balancing it by sinking the heavier side of the wheel. Sticky weights from auto stores can be used to add weight to the lightest part of the wheel. Clean edges before installing weights and recheck balance afterward. After finishing all tires. test for any remaining vibrations which may suggest other proble...

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