月: 2023年2月

What Is Cheesecloth?

Cheesecloth is a versatile agricultural covering material designed to protect crops. It shields plants from the harsh effects of the summer sun, cold temperatures, wind, and insects. Available in different materials and sizes, cheesecloth’s effectiveness depends on selecting the appropriate color for the intended purpose.

Uses of Cheesecloth

In horticulture and crop cultivation, cheesecloth serves multiple functions. It provides heat retention and windproofing, along with shading. The specific use varies with the season, aiding in seedling growth in early spring, offering light shading during summer, and protecting against frost in winter.

Characteristics of Cheesecloth

While similar to non-woven fabrics and insect nets, cheesecloth has distinct advantages and disadvantages.

Advantages

Cheesecloth is long-lasting and economical. It is affordable, available in various colors to select desired shading properties, and has excellent air permeability. This durability and versatility make it suitable for multiple purposes, including insect control and heat retention.

Disadvantages

However, its versatility can sometimes limit its effectiveness. For instance, non-woven fabrics are superior for heat retention. Black cheesecloth, while offering high shading, is less effective for heat retention. In terms of insect repellency, finer mesh or light-reflective colors in some cheesecloths are beneficial, but insect nets are more effective. Layering cheesecloth with non-woven fabrics and insect nets can optimize its functionality.

Types of Cheesecloth

Cheesecloth can be classified based on material, size, and color:

1. Classification by Material

Common materials include chemical fibers like polyethylene and natural fibers such as cotton and hemp. Polyethylene is a popular choice due to its cost-effectiveness and large-scale utility. Natural fibers, while rougher and less protective against light and wind, offer excellent air permeability, facilitating watering without removing the cover.

2. Classification by Size

Home garden varieties often come in lengths of 5m or 10m and widths of 1.35m or 1.8m. For tunneling, the length should be 1.5 to 2 times that of the rows to prevent insect intrusion.

3. Classification by Color

Available in colors like white, black, and transparent, each suited to different needs. White cheesecloth, with a low shading rate of 20%, is ideal for winter use for heat retention and frost prevention. Black cheesecloth, offering a 50% shading rate, is used in summer for shade and moisture retention. Color choice is crucial for optimal results, considering seasonal requirements and specific crop needs.

Other Information on Cheesecloth

1. How to Use Cheesecloth

Proper installation is key to maximizing cheesecloth’s effectiveness. It involves placing arch supports, covering them with cheesecloth, and securing them to prevent displacement by wind.

2. Difference Between Cheesecloth and Non-woven Fabric

Cheesecloth is primarily used for shading and protection from elements, while non-woven fabrics focus on heat retention. Insect nets, alternatively, are used solely for insect control. Each has its distinct usage based on the crop’s needs and environmental conditions.

What Is a Guardrail?

A guardrail is a protective barrier used in factories and other industrial settings to prevent or mitigate damage from vehicle collisions. With the frequent operation of forklifts, AGVs, and other vehicles, guardrails play a crucial role in averting industrial accidents and preserving the safety of workers and equipment.

While traditional safety measures focused on human-centered approaches like training and rule compliance, the adoption of guardrails as physical barriers is increasingly recognized as essential. They are key to ensuring the separation of pedestrians and vehicles in workplaces.

Uses of Guardrails

Guardrails serve two primary purposes:

1. To Protect People

Guardrails are installed to physically separate pedestrian zones from vehicle-operating areas, enhancing safety in factories where both coexist.

2. Protecting Assets

They are also employed to safeguard production equipment, transport equipment, and infrastructure like buildings, shutters, and piping against vehicle collisions.

Types of Guardrails

Guardrails at manufacturing sites come in various types, each suited to specific operational environments:

1. Simple Barrier

Simple barriers are floor-installed and act mainly as visual warnings. They are used both temporarily and permanently but don’t offer significant impact resistance.

2. Steel Barriers

Steel barriers provide a moderate level of protection but tend to deform upon impact and may damage concrete floors due to lack of shock absorption.

3. Polymer Protective Barriers

These modern barriers are made of polymer resin, known for their impact absorption and recovery properties. They offer advanced protection without the drawbacks of rusting or paint peeling and don’t damage the floor upon impact. Choosing a barrier rated for the specific impact level needed for the work environment ensures appropriate protection.

What Is a Laser Engraving Service?

A laser engraving service is a specialized technique for engraving intricate patterns or designs onto various materials. The depth and precision of the engraving depend on the material and the laser’s output power. Laser processing encompasses cutting, marking, engraving, and laser engraving services.

• Laser cutting: Primarily used for cutting materials with precise straight lines.
• Laser marking: Involves melting or scorching the surface for long-lasting prints.
• Laser engraving: Utilizes a laser to melt the surface for precise printing or engraving.
• Laser engraving service: A form of laser marking that allows detailed engraving using graphic data.

Uses for Laser Engraving Services

Laser engraving services are versatile and suitable for materials like wood, plastic, fabric, metal, acrylic, and glass. They can also handle both soft and hard materials such as rubber and stone. Engravings are durable, making them ideal for novelty items and other products where long-lasting markings are desired. The color of the engraving can vary based on material and laser intensity, with common hues including white on aluminum, gold on brass, and burnished on wood.

Principles of Laser Engraving Services

The laser engraving process involves creating design data, setting laser output, adjusting data, positioning the material, and performing the actual engraving. Design drafts are created using graphics or CAD software, and the laser settings are adjusted for intensity and speed based on the material. The final stage involves setting the material in the machine and executing the engraving based on the prepared data. Test processing is recommended to ensure quality and compatibility with the material.

What Are Noise Level Meters?

Noise level meters detect noise to protect the living environment and human health.

Noise is considered sensory pollution along with odor and vibration. It imposes sensory and psychological burdens. Noise includes automobile noise, aircraft noise, bullet train noise, conventional rail line noise, infrasound, and general environmental noise.

Uses of Noise Level Meters

Environmental standards for noise are mainly divided into three categories. In addition, there are two other categories of applicable areas, and one standard value is set as a special exception.

First, Category AA is a type of area that includes areas where noise is required, in areas where medical treatment facilities, social welfare facilities, etc. are clustered together. The standard values are divided into daytime and nighttime, with the former set at 50 decibels or fewer and the latter at 40 decibels or fewer.

Second, there are two categories, A and B. A is for areas used exclusively for residential purposes, and B is for areas used primarily for residential purposes. The standard is set at 55 decibels or fewer during the daytime and 45 decibels or fewer at night.

The third is Category C, which includes areas used for commercial and industrial purposes, in addition to a significant number of residences.

Other applicable areas include, areas fronting on roads with two or more lanes; areas fronting on roads with two or more lanes; and areas fronting on roads with two or more lanes. The former is 60 decibels or lower during the daytime and 55 decibels or lower at night. The latter is 65 decibels or fewer during the day and 60 decibels or fewer at night.

As a special exception, in the case of a strip of roadway with a certain width necessary for the safe and smooth running of vehicles in a single abreast, the standard value is 70 decibels or fewer during the daytime and 65 decibels or fewer during the nighttime in the space adjacent to a road carrying arterial traffic.

However, in the case of individual residences where windows on noise-sensitive surfaces are closed, the standard for noise transmitted indoors is 45 decibels or fewer during the daytime and 40 decibels or fewer at night.

Principles of Noise Level Meters

The first step is to determine the location of the microphone. The microphone should be located where it can avoid the influence of local shielding or reflection by moats, buildings, etc., to grasp the wide area and overall noise situation of the area.

Next, the height of the measurement point should be set at the average height of living surfaces, such as houses in the area.

As for the setting of the dynamic characteristic of the sound level meter, the time weighting characteristic is set as F characteristic, and when only the equivalent noise level is measured, either F characteristic or S characteristic setting is acceptable.

Finally, as for the processing of the sound to be excluded, when the sound to be excluded occurs by dividing the measured time into small segments during the analysis, the statistical processing is performed, excluding the data of the time segment. Sounds to be excluded include natural sounds that are not normal, artificial sounds that do not normally occur, and additional sounds caused by measurements.

What Is a Mercury Analyzer?

A mercury analyzer is a tool used for detecting the presence and concentration of mercury in environmental or biological samples. Mercury, while naturally occurring, can be harmful to human health if ingested in amounts above the permissible limit.

In 2003, the 22nd United Nations Environment Program (UNEP) Governing Council meeting highlighted the need for international efforts to curb mercury emissions, leading to the adoption of the “Minamata Convention On Mercury” by approximately 140 countries, with 92 countries, including the EU, signing the Convention.

Uses of Mercury Analyzers

Mercury analyzers play a vital role in industries where mercury was previously widely used. Today, its use is largely prohibited except in specific licensed products. The “Global Atmospheric Mercury Assessment” by UNEP in 2008 revealed that global mercury demand includes applications in small-scale gold mining, the manufacturing process of vinyl chloride monomer, the chlor-alkali industry, batteries, dental amalgam, measuring equipment, lighting, electrical equipment, and others.

Principles of Mercury Analyzers

Reliable mercury analysis requires proper sample collection and preparation, measurement methods tailored to the sample type, and careful solution preparation. Preventing external contamination, such as maintaining a clean laboratory and instruments, is crucial for accurate analysis. Distinguishing between total mercury, methylmercury, and inorganic mercury is essential for understanding mercury’s effects and its dynamics in the environment and the human body.

Reference materials for quality control and assurance of environmental and human samples are available from NIST, IAEA, NRCC, and NIES. Sample types include biological (fish and shellfish), water, sediment/soil, plant, and air samples for environmental testing, and hair, blood, urine, and umbilical cord samples for human testing.

What Is a Dioxin Testing Service?

A dioxin testing service is a method used to detect dioxins, which are byproducts of various processes such as general and industrial waste incineration facilities, electric furnaces used in steelmaking, chlorine bleaching processes in paper manufacturing, and emissions from cigarette smoke and automobile exhaust. Dioxin testing is crucial for source control and assessing environmental contamination.

The initiative to control dioxin emissions began in 1983 when dioxin was detected in fly ash from a waste incineration plant.

Uses of Dioxin Testing Services

Environmental standards for dioxin concentration include Air: an annual average of 0.6-TEQ/m3 or less, Water: an annual average of 1 pg-TEQ/l or less, Sediment: 150 pg-TEQ/g or less, and Soil: 1000 pg-TEQ/g or less. Facilities that must adhere to specific emission standards include waste incinerators with a minimum size or capacity, with different standards for new and existing facilities.

Dioxins commonly refer to polychlorinated dibenzo-para-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). Additionally, substances like coplanar polychlorinated biphenyls (coplanar PCBs), which exhibit similar toxicity to dioxins, are termed dioxin-like compounds.

Dioxins are structurally composed of two benzene rings connected by oxygen atoms and attached to chlorine atoms. There are 75 types of PCDDs, 135 types of PCDFs, and 12 types of coplanar PCBs, with 29 of these identified as toxic.

What Is a Security System?

A security system is a framework designed to protect against various dangers and security threats. It commonly refers to systems geared towards information security, which is becoming increasingly vital due to the rapid advancement of information and communication technologies.

Without adequate security measures, risks such as privacy invasion and information leaks can arise. Security systems need regular updates to combat new and evolving threats.

Uses of Security Systems

Security systems are essential for safeguarding information on devices like PCs and smartphones. They are crucial for both individuals and corporations in today’s technology-driven world, forming a vital part of the social infrastructure.

Principles of Security Systems

Security systems aim to protect information assets based on three key principles: confidentiality, integrity, and availability. These principles are often referred to as the CIA of information security:

1. Confidentiality

Ensures that information is accessible only to authorized individuals.

2. Integrity

Maintains the accuracy of information, preventing unauthorized tampering or destruction.

3. Availability

Guarantees that authorized users can access information whenever needed.

It is crucial to maintain a balance between these three aspects in implementing effective security measures.

Types of Security Systems

Security systems encompass various types of measures, including:

1. Computer Virus Countermeasures

• Implementation and regular updating of anti-virus software.
• Filtering of hazardous websites.

2. Unauthorized Access Countermeasures

• Effective password management.
• Installation of firewalls and intrusion prevention systems.
• Regular updates of security software.
• Logging and management of system access.

3. Information Leakage Prevention

• Firewall installation and management of sensitive data.
• Secure disposal of materials, media, and equipment.
• Security settings for wireless networks.
• User access and authorization management.

Additionally, backups and uninterruptible power supplies are critical for safeguarding against equipment failure during natural disasters.

Other Information on Security Systems

1. Information Security Management

Corporations must establish and regularly review an information security policy while educating staff to adhere to these protocols. This comprehensive approach is known as information security management.

2. History of Security Systems

The need for robust information security was highlighted in 2000, with the increase in cyber attacks on private companies. With the rise of remote working, the threat of ransomware targeting teleworking vulnerabilities has also escalated, making information security more critical than ever.

What Is an Ultrashort Pulse Laser?

An ultrashort pulse laser is a type of laser with extremely brief pulse widths ranging from a few picoseconds to a few femtoseconds. A picosecond is one trillionth of a second, while a femtosecond is even shorter, at one quadrillionth of a second. The extreme brevity of these pulses means that in the time it takes for a single pulse to occur, light travels only a fraction of a millimeter.

This short pulse duration makes ultrashort pulse lasers unique among pulsed lasers. These lasers produce a pulse that undergoes a large change in a very brief period, allowing for high-precision, low-thermal-impact laser processing across a wide range of materials.

Uses of Ultrashort Pulse Lasers

Ultrashort pulse lasers are particularly effective due to their high peak intensity, allowing them to interact even with transparent materials through nonlinear absorption processes like multiphoton ionization. By focusing these laser beams inside transparent materials, intricate, three-dimensional processing becomes possible.

They can be used on various materials, from hard diamonds to softer materials like glass, resins, and ceramics. The precision of ultrashort pulse lasers allows for detailed processing such as drilling, trimming, and micro-texturing without causing heat damage or burrs.

Principle of Ultrashort Pulse Lasers

Lasers can oscillate continuously (CW lasers) or in pulses. Pulsed lasers, including ultrashort pulse lasers, operate intermittently and can be modulated in various ways, such as direct, external, Q-switching, or mode-locking. Ultrashort pulse lasers typically use the mode-locking method to achieve their incredibly brief pulse widths.

Mode-Locking Method

Mode-locking can be active (forced) or passive (self-mode-locking). Active mode-locking synchronizes the phase between modes using a loss or phase modulator, while passive mode-locking uses a saturable absorber to selectively absorb the leading edge of a pulse. Both methods are essential for producing ultrashort pulse lasers.

Pricing of Ultrashort Pulse Lasers

Due to their complex design and short pulse widths, ultrashort pulse lasers are among the more expensive laser types. They are used in various applications, from microfabrication to scientific research, and typically fall in the higher price range.

History of Ultrashort Pulse Lasers

The development of lasers began with ruby lasers in the 1960s, which used pulsed oscillation. Over time, innovations like the Q-switch method and mode-locking have led to the advancement of laser technology, enabling the creation of lasers capable of producing extremely short pulses, including picosecond and femtosecond lasers.

Q-Switch Method

The Q-switch method produces high-power pulses over microseconds to nanoseconds. This method temporarily suppresses laser oscillation, building up energy before releasing it in a powerful pulse, and is used in various applications, including electronic and semiconductor processing.

YAG Laser

The YAG laser is a solid-state laser using yttrium aluminum garnet as the medium. It’s known for its manageability and efficiency in processing.

Dye Laser

Dye lasers use a liquid dye solution as the lasing medium, offering a wide range of wavelength variability and applications, including medical and industrial uses.

The evolution of these lasers over the years has led to the development of Ti: sapphire lasers and other advanced femtosecond laser systems, further expanding the capabilities and applications of ultrashort pulse lasers.

What Is a Packaging Material?

Packaging materials are used for wrapping, decorating, protecting, and transporting objects. These materials come in various forms, such as food containers, trays, plastic bags, paper bags, film packaging, paper napkins, and cushioning materials, covering a broad range of applications in manufacturing and sales, particularly in the food industry.

Uses of Packaging Materials

Packaging materials play a crucial role across many industries. Functionally, they can be divided into industrial packaging for transporting or storing goods and commercial packaging for enhancing product sales. Industrial packaging focuses on protection, delivery efficiency, and cost, while commercial packaging emphasizes aesthetic appeal to boost sales.

Industrial packaging examples include laminated products used for moisture and rust proofing, suitable for precision instruments, electrical appliances, paper, wood, clothing, and metal products. These are also used as export packaging and packing materials. Laminates often incorporate materials like aluminum foil, polyethylene (PE), and polyethylene terephthalate (PET).

Commercial packaging, such as gift wrapping, allows for creative design tailored to consumer preferences, using materials like paper, cloth, polypropylene (PP), and cardboard.

Principles of Packaging Materials

The packaging materials industry is continually evolving, especially with increasing research into plastics, driven by concerns over crude oil consumption and marine pollution.

Plastics, organic polymeric materials with plasticity, can be molded into various shapes upon heating. They are mainly categorized into thermoplastics and thermosets. Commonly used plastics in containers and packaging include polyethylene (PE), polypropylene (PP), polystyrene (PS), and polyethylene terephthalate (PET).

Plastics are also valued for their barrier properties, preventing harmful substances like gas, moisture, and odors from affecting the packaged contents. Polyvinylidene chloride (PVDC) is a notable barrier material, although its usage is decreasing due to environmental concerns. Alternatives such as inorganic vapor-deposited films, polyamide, and three-layer nylon with ethylene vinyl alcohol copolymer (EVOH) are gaining prominence.

What Is a Rubber Coating?

A rubber coating refers to a protective coating technology for rubber. Rubber coatings involve not just painting, but also address issues like hydrolysis and plasticizer migration, which can cause the coating to become sticky and transfer color to other molded products.

There are many different types of rubber, and manufacturers use varying methods to produce them. Additionally, rubber dissolves in organic solvents such as thinners, necessitating special care when using such solvents. Therefore, rubber coatings are challenging to handle, with potential issues like poor adhesion, even within the same type of rubber.

However, with recent advancements in technology, there are now a variety of paints available for rubber, reducing the likelihood of post-coating problems.

Uses of Rubber Coatings

Rubber coatings are used in various everyday products and industrial applications. For example, rubber switches for remote controls are often coated to provide heat resistance, water resistance, chemical resistance, weather resistance, and improved user convenience.

Other industrial applications include rubber fences in baseball fields, tennis courts, and harbors. These fences are used to absorb impacts and prevent injuries, as well as to block floating debris in ports and harbors. Rubber coatings on these fences, often utilizing polyethylene or polyurethane foam, enhance gloss, abrasion resistance, and scratch resistance, and improve visibility and landscaping.

Principles of Rubber Coating

Rubber coatings should be selected based on the object and environment in which they are applied, using traditional oils and raw materials produced as petroleum by-products. There are various types of rubber-based paints available, including natural rubber (NR), synthetic natural rubber (IR), butadiene rubber (BR), styrene butadiene rubber (SBR), and butyl rubber (IIR), among others.

Other types of paints include oil-based paints, liquor paints, synthetic dry oil paints, synthetic resin paints, and graft copolymers, each with distinct characteristics and applications.

1. Oil-Based Paints

Oil-based paints, using sulfide oils such as linseed oil, sulfur, terpene oil, and benzine, have been traditionally used for rubber shoes.

2. Liquor Paint

Liquor paint, used for tires, raincoats, and upholstery, employs colophonium, terpene oil, shellac, sandalac, etc.

3. Synthetic Dry Oil Paints

Synthetic dry oil paints, made from oligomers of olefins produced as petrochemical byproducts, are modified with rubber to provide elasticity to coatings.

4. Synthetic Resin Coatings

Synthetic resin paints, consisting mainly of alkyd resin, vinyl resin, epoxy resin, silicone resin, fluorine resin, and polyurethane resin, are dissolved in organic solvents like benzene.

5. Graft Copolymer

Graft copolymers combine the properties of rubber and resin in a paint vehicle for rubber, often used for rubber footwear. They are produced by adding a vinyl monomer to a rubber solution and initiating a vinyl polymerization reaction with a radical initiator.