High-Quality Serological Pipette Tips for Accurate Laboratory Testing

Sterile Non-Treated U-Bottom 96-Well Cell Culture Plates - Pack of 100

IntroductionCell culture is an essential technique used in many fields, including biotechnology, medical research, and pharmaceutical research. It involves growing and maintaining cells from different organisms under controlled conditions in a laboratory setting. Researchers use cell culture plates to cultivate cells efficiently.In this blog, we will discuss 96-well cell culture plates, particularly U-bottom, non-treated, sterile plates, and their use in cell culture applications.What is a 96-Well Cell Culture Plate?A 96-well cell culture plate is a multi-well plate used to grow and maintain cells in vitro. It consists of a plastic plate with 96 individual wells, each with a capacity of 0.32 ml. The wells are arranged in a 12 x 8 matrix, which makes it easy for researchers to handle and analyze multiple samples simultaneously.U-Bottom vs. Flat-Bottom PlatesOne of the critical differences between cell culture plates is the shape of the bottom of the wells. U-bottom plates have a U-shape bottom, which provides more surface area for cell growth and better cell retention compared to flat-bottom plates. Additionally, U-bottom plates are useful for applications such as sedimentation assays and suspension cell culture.Non-Treated vs. Treated PlatesCell culture plates can either be treated or non-treated. Non-treated plates have no surface treatment, which allows researchers to covalently attach various coatings, such as extracellular matrix proteins or growth factors, to the wells. This feature makes non-treated plates ideal for cell differentiation studies and applications that require specific cell culture conditions.On the other hand, treated plates come with a surface treatment that enhances cell attachment. For instance, poly-L-lysine or collagen coatings improve adhesion, while poly-D-lysine coatings facilitate in suspension culture applications. Treated plates are suitable for standard cell culture and analysis experiments.SterilizationCell culture plates must be sterile to prevent contamination by unwanted microbes. Manufacturers use various sterilization techniques, such as gamma irradiation, ethylene oxide treatment, and autoclaving, to ensure sterility. Additionally, the plates are packaged in a controlled environment to prevent contamination during shipping and storage.ApplicationsCell culture plates have numerous applications in various fields. Here are some of the common applications of 96- well cell culture plates:1. Drug DiscoveryCell culture plates are used extensively in the drug discovery process to screen potential drug candidates for their efficacy and toxicity. The 96-well format allows for high throughput screening of multiple compounds simultaneously.2. Cell-Based AssaysCell-based assays are used to measure cellular responses to different stimuli, including drugs, toxins, and environmental changes. The 96-well format allows for the measurement of multiple assays simultaneously.3. Stem Cell ResearchStem cell research requires specialized culture conditions, such as specific extracellular matrix coatings, to maintain cell viability and differentiation. Non-treated 96-well plates provide researchers with the flexibility to coat the wells with their preferred coatings for better stem cell culture.Conclusion96-well cell culture plates are versatile tools in cell culture applications. The U-bottom, non-treated, sterile plates offer a high surface area for cell attachment, better cell retention, and flexibility to customize the culture conditions. In addition, the 96-well format allows for high-throughput screening and simultaneous analysis of multiple samples. When choosing the right cell culture plate, it's essential to consider the application, surface treatment, and shape of the bottom for optimal cell culture conditions.

Top 6 Reverse Osmosis Systems for Clean Water Filtration in 2021

Reverse osmosis systems have become increasingly popular in recent years due to their effectiveness in removing contaminants from drinking water. This filtration method uses a semi-permeable membrane to remove impurities such as bacteria, viruses, dissolved solids, and heavy metals from tap water. Among the various types of reverse osmosis systems available in the market, filter reverse osmosis systems have emerged as one of the most effective and efficient options.According to a recent report, filter reverse osmosis systems have seen a surge in demand over the past year, with consumers becoming increasingly aware of the importance of clean drinking water. These systems not only provide safe and healthy water but also offer a cost-effective alternative to bottled water. The report suggests that the market for filter reverse osmosis systems is expected to grow significantly in the coming years.One of the key factors driving the demand for filter reverse osmosis systems is their ability to remove a wide range of contaminants. Unlike traditional water filters, which only remove larger particles, these systems use a multi-stage filtration process that can remove even the smallest impurities. This ensures that the water you drink is free from harmful substances that can affect your health in the long run.Another advantage of filter reverse osmosis systems is their low maintenance cost. These systems typically require a filter change every 6 to 12 months, depending on the water quality in your area. This not only saves you money but also reduces wastage as the filters can be recycled.Several brands offer filter reverse osmosis systems, each with its unique features and specifications. When choosing a system, it is essential to consider factors such as the water quality in your area, the size of the system, and your budget. Some of the popular models in the market include (need to remove brand names).Company IntroductionOur company is a leading provider of water filtration solutions, with a focus on reverse osmosis systems. We have been in the business for over a decade and have established a reputation for providing high-quality products that meet our customers' needs. Our team of experts has extensive knowledge of the latest filtration technologies, enabling us to offer cutting-edge solutions that deliver safe and healthy water.We offer a wide range of filter reverse osmosis systems, suitable for different applications and budgets. Our systems use advanced filtration technologies that remove even the smallest impurities, ensuring that you get safe and healthy water every time. We also offer filter replacement services, ensuring that your system continues to function optimally.Our commitment to quality is evident in everything we do, from the products we offer to the services we provide. We are dedicated to providing our customers with the best possible experience, and our team of experts is always available to offer advice and support.ConclusionFilter reverse osmosis systems are an effective and efficient way to get clean and healthy drinking water. With the increasing demand for safe and affordable water, these systems have become an increasingly popular choice among consumers. Whether you are looking to improve the quality of your tap water or reduce your reliance on bottled water, a filter reverse osmosis system can provide an effective solution. Contact us today to learn more about our range of systems and how we can help you get safe and healthy water.

Gigantic Petri Dish Shows Bacteria Evolving Antibiotic Resistance

The rectangular petri dish has been a staple tool in microbiology laboratories for over a century. It was first invented by Julius Richard Petri in 1877, and since then it has been used to grow and observe bacteria, fungi, and other microorganisms. However, researchers from Harvard Medical School and Technion-Israel Institute of Technology have taken the use of petri dishes to a whole new level.They have build a gigantic rectangular petri dish, measuring over two meters long and half a meter wide. This petri dish is not just impressive in size, but also in the way it visualizes the evolution of bacteria. The researchers coated the dish with a gel containing both antibiotics and a nutrient source for the bacteria to grow on. They then created a gradient of antibiotic concentration across the gel, so that the bacteria could gradually adapt and evolve to become antibiotic-resistant.The result is a stunning and terrifying visualisation of how bacteria can quickly adapt to new environments and develop resistance to drugs. As the bacteria move across the dish, they encounter higher and higher concentrations of antibiotics, which kills off weaker and more susceptible bacteria. However, the few bacteria that are already resistant to the antibiotics survive and thrive, and they pass on their resistance genes to their offspring.Over time, the petri dish becomes a landscape of bacterial colonies, each with their own distinct shape, color, and resistance level. Some bacteria form clusters and tendrils, while others spread out in a smooth and even layer. Some bacteria turn bright green, while others remain red or yellow. The most striking thing about this petri dish is that it shows how quickly and dramatically bacteria can change and adapt to new conditions.This research has important implications for the ongoing problem of antibiotic resistance. Antibiotics have been one of the greatest medical advancements of the past century, but their overuse and misuse has led to the emergence of superbugs that are resistant to most or all antibiotics. This makes it harder and harder to treat infectious diseases and puts millions of lives at risk.By visualizing the process of bacterial evolution in a rectangular petri dish, this research highlights the urgent need for smarter and more responsible use of antibiotics. It also provides new insights into how bacteria evolve and adapt, which could help researchers develop new strategies for combating antibiotic resistance.In conclusion, the gigantic rectangular petri dish created by the researchers from Harvard Medical School and Technion-Israel Institute of Technology is a powerful and fascinating tool for visualizing the evolution of bacteria and understanding the problem of antibiotic resistance. It is a reminder that the world of microorganisms is constantly changing and adapting, and that we need to keep up with them if we want to stay ahead of the curve.

Optimizing Adherent Cell Culture Flasks: Enhancing Cell Growth and Viability

Title: Revolutionizing Cell Culture: Introducing the Innovative Adherent Cell Culture FlasksIntroduction:In the rapidly advancing field of biotechnology, adherent cell culture plays a pivotal role in a wide range of applications, from drug discovery and development to tissue engineering and regenerative medicine. Recognizing the limitations of traditional culture vessels, renowned biotech leader (company name), has unveiled its groundbreaking Adherent Cell Culture Flask, revolutionizing the way researchers cultivate and manipulate adherent cells. This cutting-edge solution promises improved efficiency, enhanced cell viability, and simplified cell culture protocols, opening new avenues for scientific breakthroughs and medical advancements.1. The Problem: Overcoming the Limitations of Traditional Culture VesselsConventional cell culture flasks have been the standard choice for cultivating adherent cells. However, these vessels often pose significant limitations that hinder experimental reproducibility and yield suboptimal results. Limited surface area, insufficient gas and nutrient exchange, and challenging scalability are a few of the challenges that scientists encounter. As cell culture technology continues to progress, the need for more advanced culture systems has become paramount.2. The Solution: Introducing the Adherent Cell Culture FlaskThe Adherent Cell Culture Flask, developed by (company name), addresses the shortcomings of traditional culture vessels while introducing innovative features for improved cell growth and manipulation. This breakthrough solution aims to optimize cell culture conditions and streamline workflows to enhance research efficiency and maximize scientific outcomes.a. Enhanced Surface Area: The Adherent Cell Culture Flask offers an expanded growth surface, providing ample area for adherent cells to grow and flourish. This increased surface area allows for higher cell yields and reduces the need for regular passaging, ultimately saving time and resources in long-term experiments.b. Superior Gas and Nutrient Exchange: The advanced design of the flask allows for optimal oxygen and nutrient diffusion, ensuring the cells receive consistent nourishment throughout the culture duration. This improved gas and nutrient exchange promotes cell health, viability, and proliferation, contributing to more reliable experimental results.c. Simplified Handling: The Adherent Cell Culture Flask incorporates an ergonomic design, making cell seeding, cultivation, and medium changes effortless. The flask's user-friendly features streamline cell culture protocols, reducing the risk of contamination and minimizing hands-on time for researchers. This simplified handling enables scientists to focus more on the experimentation process itself.d. Scalability: Recognizing the increasing need for large-scale cell culture, (company name) has engineered the Adherent Cell Culture Flask to accommodate scalable applications. Researchers now have the flexibility to expand their experiments and seamlessly adapt to various cell culture demands, without compromising productivity or compromising cellular integrity.3. Conclusion: Pioneering the Future of Adherent Cell CultureWith the introduction of the innovative Adherent Cell Culture Flask, (company name) sets a new standard in the field of cell biology and biotechnology. By addressing the limitations of traditional culture vessels, this groundbreaking solution opens doors to countless research opportunities and paves the way for significant advancements in scientific research, drug development, and regenerative medicine.Powered by (company's vision and expertise), the Adherent Cell Culture Flask combines cutting-edge technology, user-friendly design, and scalability to enable researchers worldwide to push the boundaries of cellular research. With this groundbreaking innovation, (company name) continues to empower scientists with the tools they need to unlock the mysteries of life and shape the future of medical science.

Affordable 100mm Petri Dish for Scientific Research in China

China Petri Dish 100mm, a leading manufacturer in the field of laboratory consumables, has recently launched their latest product, the 100mm Petri Dish, with the aim of providing high-quality and reliable laboratory equipment for the global scientific community.With over 20 years of experience in the industry, China Petri Dish 100mm has established itself as a trusted name in the field of laboratory consumables. The company is committed to providing innovative and cutting-edge solutions for researchers and scientists, and their latest product is a testament to their dedication to excellence.The 100mm Petri Dish is specifically designed to meet the growing demands of modern laboratory research. Made from high-quality, transparent plastic, the dish offers superior clarity and visibility, allowing for accurate observations and measurements. The dish also features a flat, optically clear surface, ensuring optimal cell attachment and growth for a wide range of applications, including cell culture, microbiology, and molecular biology.In addition, the 100mm Petri Dish is compatible with a variety of laboratory equipment, making it a versatile and practical solution for researchers and scientists. The dish is also designed for ease of use, with a durable construction that allows for easy handling and stacking, making it ideal for high-throughput and automated applications.Furthermore, China Petri Dish 100mm is committed to sustainable and environmentally friendly practices. The company utilizes state-of-the-art manufacturing processes and materials that are eco-friendly and comply with international standards. This commitment to sustainability ensures that their products not only meet the highest quality standards, but also have a minimal impact on the environment.“We are thrilled to introduce our latest product, the 100mm Petri Dish, to the global scientific community,” said a spokesperson for China Petri Dish 100mm. “With its superior quality and design, we believe that this product will make a significant impact on laboratory research and contribute to advancements in science and medicine.”The launch of the 100mm Petri Dish underscores China Petri Dish 100mm’s ongoing commitment to providing innovative and reliable laboratory equipment to researchers and scientists worldwide. The company’s reputation for excellence and dedication to quality make them a trusted partner for laboratories and research facilities around the world.As the demand for high-quality laboratory consumables continues to grow, China Petri Dish 100mm remains at the forefront of the industry, offering innovative solutions and exceptional customer service. With their latest product, the 100mm Petri Dish, the company is poised to make a significant impact on the field of laboratory research, further solidifying their position as a leader in the market.In conclusion, China Petri Dish 100mm’s launch of the 100mm Petri Dish represents a significant advancement in the field of laboratory consumables. With its superior quality, versatility, and commitment to sustainability, the dish is poised to become a valuable tool for researchers and scientists worldwide, further solidifying China Petri Dish 100mm’s position as a trusted and innovative provider of laboratory equipment.

Discover the Benefits of a Large Erlenmeyer Flask for Your Needs

Title: Innovative Large Erlenmeyer Flask Revolutionizes Laboratory Practices Introduction: In a breakthrough development that promises to transform laboratory practices across various scientific disciplines, a pioneering company has unveiled its latest creation - an innovative Large Erlenmeyer Flask designed to optimize experimental procedures and enhance research efficiency. This revolutionary product, developed by [Company Name], exemplifies the company's commitment to pushing the boundaries of scientific experimentation and delivering cutting-edge solutions to the scientific community. [Company Name], a renowned leader in laboratory equipment manufacturing, has a rich legacy of innovation and excellence. With a dedicated team of scientists and engineers, the company has consistently developed products that cater to the evolving needs of modern laboratories worldwide. Their latest offering has already garnered significant attention in the scientific community due to its groundbreaking features and potential to revolutionize laboratory practices. I. Redefining Laboratory Equipment:The [Company Name] Large Erlenmeyer Flask is a game-changer in the realm of laboratory equipment. Created with meticulous attention to detail, this flask is engineered to address the inefficiencies and limitations of traditional Erlenmeyer flasks commonly used in laboratories. Featuring a design that emphasizes ergonomics, durability, and functionality, the flask provides scientists and researchers with an unparalleled tool for their experimental work.II. Enhanced Design and Features:The Large Erlenmeyer Flask boasts several innovative features that optimize scientific experimentation. Firstly, its enlarged size enables a greater volume capacity, leading to increased efficiency and reduced frequency of sample transfers. Additionally, the flask's robust construction ensures longevity and enables it to withstand the rigorous demands of laboratory environments.Furthermore, the flask incorporates a unique secure grip design, making it easier and safer to handle, particularly when dealing with heated substances or volatile chemicals. The flask's wide-mouthed opening facilitates easy pouring, further streamlining laboratory procedures and reducing the risk of spills or accidents. III. Versatility and Adaptability:One distinct advantage of the [Company Name] Large Erlenmeyer Flask is its adaptability across multiple scientific disciplines. From biochemistry to pharmaceutical research, this flask can accommodate a wide range of applications and experimental requirements. Its compatibility with various experimental setups and equipment makes it an essential asset for researchers and scientists seeking reliable and versatile laboratory equipment.IV. Impact on Research Efficiency:By eliminating the need for frequent transfers and providing enhanced reliability, the Large Erlenmeyer Flask significantly improves research efficiency. Researchers can save valuable time and resources by conducting experiments seamlessly, without interruption or compromise. This accelerated workflow not only facilitates groundbreaking discoveries but also contributes to scientific progress overall.V. Commitment to Sustainability:Aside from its benefits to laboratory practices, the [Company Name] Large Erlenmeyer Flask is also designed in line with the company's commitment to sustainability. Manufactured using eco-friendly materials and adhering to responsible production practices, this flask embodies [Company Name]'s dedication to reducing its environmental footprint while delivering impeccable scientific equipment.VI. Future Prospects:The debut of the Large Erlenmeyer Flask marks a significant milestone for [Company Name] and the scientific community at large. By pushing the boundaries of traditional laboratory equipment, [Company Name] continues to set new standards for quality and functionality. With ongoing research and development efforts, the company aims to further refine and expand the capabilities of this revolutionary product, driving innovation and progress in scientific experimentation.In conclusion, the introduction of the Large Erlenmeyer Flask by [Company Name] represents an exciting leap forward in laboratory practices. With its groundbreaking features, unmatched adaptability, and demonstrated impact on research efficiency, this innovative flask has the potential to revolutionize scientific experimentation across various disciplines. [Company Name] continues to exemplify its dedication to excellence through its commitment to sustainable manufacturing and consistently pushing the boundaries of scientific equipment design.

Revolutionary Liquid Handling Products for Improved Data Quality

Improving Your Data Quality with Biotix TipsIn the world of science and research, data quality is of paramount importance. Accurate and reliable data is essential for making informed conclusions and advancing scientific progress. However, data quality can be compromised by poor laboratory practices or suboptimal equipment. That's why it's essential to use the highest quality liquid handling products, such as Biotix Tips, to ensure the integrity and accuracy of your results.Biotix Tips are a critical component of liquid handling systems, used for precise measurement and dispensing of liquids. What sets Biotix Tips apart from other brands is their innovative design and strict quality control measures. Biotix Tips are made with high-quality materials and manufactured under best-class standards to ensure consistency and reproducibility.One of the primary advantages of Biotix Tips is their Universal Tip Compatibility. Biotix Tips are designed to fit most pipettes, making them a versatile option for laboratories that use multiple pipette brands. This compatibility reduces the need for stocking multiple types of tips and eliminates the risk of using an incorrect tip.Another significant advantage of Biotix Tips is their low retention feature. The unique design of the tips allows for minimal liquid loss, reducing sample waste and ensuring accurate measurements. With conventional tips, residual liquid can remain in the tip, leading to cross-contamination, carry-over, and inaccurate measurements. Biotix Tips reduce this risk, improving the accuracy and reliability of your results.Biotix Tips also come with pre-sterilized packaging, ensuring aseptic conditions and reducing the risk of contamination. The packaging is designed to minimize waste and preserve the integrity of the tips until they are used, enhancing the shelf life of the product.In conclusion, the quality of your data depends on the quality of the liquid handling products you use. Using high-quality products, such as Biotix Tips, can significantly improve the accuracy and reliability of your results. With their innovative design, strict quality control measures, and compatibility with most pipettes, Biotix Tips are an excellent choice for any laboratory looking to improve their data quality.

Top Tubular Centrifuge Supplier & Manufacturer in China - Product List

Title: Exploring the Efficiency and Reliability of Tubular Centrifuge in ChinaIntroduction:In recent years, industrial centrifugation has emerged as a crucial process in various industries, from pharmaceuticals to food and beverage, and many others. Tubular centrifuges, in particular, have gained significant popularity due to their superior efficiency and reliable performance. Today, we will delve into the world of tubular centrifuges, highlighting their key features, benefits, and why China has become a leading manufacturer of these cutting-edge machines.Understanding Tubular Centrifuge:Tubular centrifuges are innovative pieces of equipment designed to separate solid particles from liquid/solids mixtures using centrifugal force. They utilize high rotational speed to generate a strong centrifugal field, ensuring the efficient separation of substances of varying densities. The unique design of these centrifuges enables continuous and simultaneous separation of multiple components within a short period, making them highly sought after in numerous industries.Superior Features of Tubular Centrifuges:1. Diverse Applications: Tubular centrifuges find extensive applications in the separation of solids from liquids, liquid-liquid separations, and even liquid-liquid-solid separation. They are widely used in sectors such as biotechnology, pharmaceutical industries, breweries, dairy plants, wastewater treatment plants, and many more.2. High Separation Efficiency: The efficient separation offered by tubular centrifuges results from their ability to generate high centrifugal forces, up to 20,000 times that of gravity. This force allows for the quick separation of solid particles, ensuring the production of pure and high-quality end products with minimal impurities.3. Continuous Operation: One of the key advantages of tubular centrifuges is their ability to operate continuously. This allows for a consistent and uninterrupted workflow, reducing downtime and enhancing overall productivity.4. Compact Design: Tubular centrifuges are renowned for their compact and space-saving design. This feature enables easy installation, mobility, and integration into existing production lines. Manufacturers in China are known for their expertise in designing and building compact centrifuges without compromising on functionality.China as a Leading Manufacturer of Tubular Centrifuges:China has emerged as a global powerhouse when it comes to manufacturing tubular centrifuges. The rapid growth of the Chinese industrial sector, coupled with advanced engineering capabilities and a skilled workforce, has resulted in the country becoming a preferred destination for these state-of-the-art machines. Chinese manufacturers are at the forefront of tubular centrifuge production, providing top-quality solutions to industries worldwide.Key Advantages of China Tubular Centrifuges:1. Competitive Pricing: The manufacturing cost advantage in China enables the production of tubular centrifuges at highly competitive prices. This affordability attracts buyers from all over the world, making China a favorite hub for procuring these essential machines.2. Large Scale Production: China has a well-established manufacturing infrastructure capable of handling large scale production. This capacity allows Chinese manufacturers to fulfill the growing demands of global industries efficiently.3. Advanced Technology: Chinese manufacturers have continually invested in research and development, leading to the adoption of cutting-edge technologies in tubular centrifuge production. This commitment to innovation ensures that China remains ahead of the curve, manufacturing centrifuges with enhanced efficiency, reliability, and performance.Conclusion:Tubular centrifuges have revolutionized industrial separation processes, providing highly efficient and reliable solutions to a wide range of sectors. China's emergence as a leading manufacturer of tubular centrifuges is a testament to the country's manufacturing prowess and commitment to delivering top-quality equipment. With their competitive pricing, large-scale production capabilities, and advanced technology, Chinese manufacturers are poised to drive the future of tubular centrifuge production, catering to the growing global demand for these remarkable machines.

What is a Pipettor? Definition and Uses of Narrow Calibrated Tubes for Liquid Transfer and Measurement

(New York, NY) - Today, the renowned laboratory equipment manufacturer announced the release of their latest product - the Advanced Pipettor. This state-of-the-art pipettor is an indispensable tool for scientists and researchers in the medical, pharmaceutical, and chemical industries. The Advanced Pipettor is a highly accurate, easy-to-use liquid-handling instrument designed to streamline laboratory workflows and enhance productivity.The pipettor is a narrow, calibrated tube that is used to transfer small amounts of liquid with precision and accuracy. This vital piece of equipment is used in a wide variety of laboratory applications, including sample preparation, chemical analysis, and drug discovery. Pipettors are crucial for ensuring accurate and reliable results for experiments and analyses that require precise measurements of liquids.'s Advanced Pipettor is the latest addition to the company's lineup of laboratory equipment. It features cutting-edge technology that has been engineered with precision and accuracy in mind. The Advanced Pipettor is designed to make liquid handling as efficient and accurate as possible. With its easy-to-use interface, the pipettor can be operated by both experienced and novice users.The main advantage of the Advanced Pipettor is its accuracy. It features an advanced, motorized piston that automatically adjusts to changes in viscosity and temperature, providing highly accurate and repeatable results. The pipettor also has a range of volume settings, allowing users to handle a wide range of sample volumes with ease. Its ergonomic design ensures that users can handle the pipettor comfortably for extended periods of use, reducing the risk of errors and user fatigue.The Advanced Pipettor is the culmination of years of research and development. It has been designed to meet the needs of scientists and researchers in a wide range of applications, said a spokesperson for . We are confident that this innovative instrument will help our customers to reduce errors, increase productivity, and achieve more accurate results.The launch of the Advanced Pipettor is just the latest addition to the company's impressive lineup of laboratory equipment. is renowned for its commitment to innovation, quality, and precision, and its products are trusted by researchers and scientists around the world. The company offers a wide range of laboratory equipment, including centrifuges, balances, spectrophotometers, and more.At a time when researchers and scientists are facing unprecedented challenges, is committed to providing the best possible equipment and support. The Advanced Pipettor is just the latest example of the company's commitment to innovation and excellence. With its advanced technology and user-friendly design, the pipettor is poised to become a vital tool for researchers and scientists across a wide range of applications.

Explore Tissue Culture for Crop Cultivation on the Largest Agricultural Portal