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Topic Review
Gallate-Based Metal–Organic Frameworks
Within three decades of fundamental findings in research on metal–organic frameworks (MOFs), a new family of hybrid materials known as gallate-based MOFs, consisting of metal salt and gallic acid, have been of great interest. Due to the fact that gallic acid is acknowledged to display a range of bioactivities, gallate-based MOFs have been initially expended in biomedical applications. Recently, gallate-based MOFs have been gradually acting as new alternative materials in chemical industrial applications, in which they were first reported for the adsorptive separation of light hydrocarbons. These porous materials have a bright future and can be kept in development for variety of applications in order to be applied in real industrial practices. 
  • 2.0K
  • 01 Dec 2020
Topic Review
Β-lactam Antibiotic
β-lactam antibiotics (beta-lactam antibiotics) are antibiotics that contain a beta-lactam ring in their molecular structure. This includes penicillin derivatives (penams), cephalosporins and cephamycins (cephems), monobactams, carbapenems and carbacephems. Most β-lactam antibiotics work by inhibiting cell wall biosynthesis in the bacterial organism and are the most widely used group of antibiotics. Until 2003, when measured by sales, more than half of all commercially available antibiotics in use were β-lactam compounds. The first β-lactam antibiotic discovered, penicillin, was isolated from a rare variant of Penicillium notatum (since renamed Penicillium chrysogenum). Bacteria often develop resistance to β-lactam antibiotics by synthesizing a β-lactamase, an enzyme that attacks the β-lactam ring. To overcome this resistance, β-lactam antibiotics can be given with β-lactamase inhibitors such as clavulanic acid.
  • 2.0K
  • 24 Nov 2022
Topic Review
Hard Tissue Engineering
Hard tissues, e.g., bone, are mechanically stiff and, most typically, mineralized. To design scaffolds for hard tissue regeneration, mechanical, physico-chemical and biological cues must align with those found in the natural tissue. Combining these aspects poses challenges for material and construct design.  They can be fulfilled in top-down tissue engineering or bottom up biofabrication approaches upon employing biomaterials e.g. silk.
  • 2.0K
  • 18 Mar 2021
Topic Review
Microfluidics in Gas Sensing
Rapid, real-time, and non-invasive identification of volatile organic compounds (VOCs) and gases is an increasingly relevant field, with applications in areas such as healthcare, agriculture, or industry. Ideal characteristics of VOC and gas sensing devices used for artificial olfaction include portability and affordability, low power consumption, fast response, high selectivity, and sensitivity. Microfluidics meets all these requirements and allows for in situ operation and small sample amounts, providing many advantages compared to conventional methods using sophisticated apparatus such as gas chromatography and mass spectrometry. This review covers the work accomplished so far regarding microfluidic devices for gas sensing and artificial olfaction. Systems utilizing electrical and optical transduction, as well as several system designs engineered throughout the years are summarized, and future perspectives in the field are discussed.
  • 2.0K
  • 20 Oct 2020
Topic Review
Pyridone Disperse Dyes Provide Added-Value
This entry provides a description of some of the disperse dyes based on pyridone and the uses of these disperse dyes as antioxidants and anticancer, as well as the use of polyester fabrics dyed with these dyes in various activities, especially medical activities. It is blamed that the textile industry is one of the major generators of industrial waste due to large quantities of water that contains a variety of pollutants, including dyes. So, our aim in this review is to explain that the dyeing process using high temperature and high pressure method was an environmentally friendly process. Therefore, this review provides a good data for chemists, biologists and interested people working in textile chemistry, public health and environment research areas.
  • 2.0K
  • 14 Sep 2020
Topic Review
Annatto
Annatto (/əˈnætoʊ/ or /əˈnɑːtoʊ/) is an orange-red condiment and food coloring derived from the seeds of the achiote tree (Bixa orellana), native to tropical America. It is often used to impart a yellow or orange color to foods, but sometimes also for its flavor and aroma. Its scent is described as "slightly peppery with a hint of nutmeg" and flavor as "slightly nutty, sweet and peppery". The color of annatto comes from various carotenoid pigments, mainly bixin and norbixin, found in the reddish waxy coating of the seeds. The condiment is typically prepared by grinding the seeds to a powder or paste. Similar effects can be obtained by extracting some of the color and flavor principles from the seeds with hot water, oil, or lard, which are then added to the food. Annatto and its extracts are now widely used in an artisanal or industrial scale as a coloring agent in many processed food products, such as cheeses, dairy spreads, butter and margarine, custards, cakes and other baked goods, potatoes, snack foods, breakfast cereals, smoked fish, sausages, and more. In these uses, annatto is a natural alternative to synthetic food coloring compounds, but it has been linked to rare cases of food-related allergies. Annatto is of particular commercial value in the United States because the Food and Drug Administration considers colorants derived from it to be "exempt of certification".
  • 2.0K
  • 20 Oct 2022
Topic Review
Sol–Gel Ceramics
The process of inorganic polymerization or the sol–gel method is an inexpensive, low-energy consuming, and stable process for obtaining high-purity ceramics, which offer versatility for the production of different kinds of devices, some of which can be used in surface-enhanced spectroscopy such as Surface Enhanced Infrared Absorption Spectroscopy (SEIRAS) and Surface Enhanced Raman Spectroscopy (SERS).
  • 2.0K
  • 22 Apr 2021
Topic Review
Protein–Polysaccharide Complexes (Conjugates) as Delivery Systems
Due to their combination of featured properties, protein and polysaccharide-based carriers show promising potential in food bioactive ingredient encapsulation, protection, and delivery. The common types of protein–polysaccharide complex/conjugate-based bioactive ingredient delivery systems include emulsion (conventional emulsion, nanoemulsion, multiple emulsion, multilayered emulsion, and Pickering emulsion), microcapsule, hydrogel, and nanoparticle-based delivery systems. This entry highlights the applications of protein–polysaccharide-based delivery vehicles in common bioactive ingredients including polyphenols, food proteins, bioactive peptides, carotenoids, vitamins, and minerals. The loaded food bioactive ingredients exhibited enhanced physicochemical stability, bioaccessibility, and sustained release in simulated gastrointestinal digestion. 
  • 2.0K
  • 04 Mar 2022
Topic Review
Gilsonite-Modified Bitumen
Hot mix asphalt has various benefits such as good workability and durability. It is one of the most general materials used as asphalt mixtures in road pavements. Asphalt mixtures and binders can be improved by modifying them with various additives. Gilsonite is a natural asphalt hydrocarbon which may be used as an additive to hot mix asphalt. It is used as an asphalt binder modifier (wet process) and an asphalt mixture modifier (dry process) to improve the properties of the mix. It provides the option of improved rheological properties, stability, strength rutting resistance and moisture sensitivity. 
  • 2.0K
  • 16 Jun 2021
Topic Review
Electrostatic Nanoassembly of Novel Composites
Electrostatic assembly is one of the bottom–up approaches used for multiscale composite fabrication. Since its discovery, this method has been actively used in molecular bioscience as well as materials design and fabrication for various applications. Despite the recent advances and controlled assembly reported using electrostatic interaction, the method still possesses vast potentials for various materials design and fabrication. This review article is a timely revisit of the electrostatic assembly method with a brief introduction of the method followed by surveys of recent advances and applications of the composites fabricated. Emphasis is also given to the significant potential of this method for advanced materials and composite fabrication in line with sustainable development goals. Prospective outlook and future developments for micro-/nanocomposite materials fabrication for emerging applications such as energy-related fields and additive manufacturing are also mentioned.
  • 2.0K
  • 11 Nov 2020
Biography
Matthew H. Todd
Matthew Houghton Todd (born 13 January 1973) is a British chemist and the Professor and Chair of Drug Discovery of the School of Pharmacy at University College London.[1] He is the founder of Open Source Malaria (OSM) and his research focuses on drug discovery and development for this disease.[2][3][4][5][6] Recently, he has expanded to other areas, particularly neglected diseases such as tuberc
  • 2.0K
  • 23 Nov 2022
Topic Review
Hazards from Burning Impregnated Wood
In the construction industry, a variety wooden products have been used for thousands of years, according to demand, accessibility/availability, and customers’ requirements. Wood is a preferred material due to its large range of properties, depending on the type of wood. It is an easily available and economically competitive material, and also extremely strong in relation to its weight. Therefore, it is used in the production of construction materials, building parts, and finishing components, as well as for furniture and decorative elements. Each of these products is commonly additionally chemically treated to improve its performance parameters. But impregnated wooden products such as furniture and fence boards are often misused, including for house heating, waste incineration, bonfires. etc. For this reason, among the products of combustion there is a whole range of different chemical compounds, frequently carcinogenic, and dangerous for health and the environment, for example heavy metals. Knowledge in this field is important for professions such as: firefighter, lifeguard, people dealing with environmental management, units responsible for waste landfills. On the other hand, important recipients of this information are ordinary residents who, due to a lack of knowledge, use such materials as e.g. heating material.
  • 2.0K
  • 29 Oct 2020
Topic Review
Biometal
Biometals are metals normally present, in small but important and measurable amounts, in biology, biochemistry, and medicine. The metals copper, zinc, iron, and manganese are examples of metals that are essential for the normal functioning of most plants and the bodies of most animals, such as the human body. A few (calcium, potassium, sodium) are present in relatively larger amounts, whereas most others are trace metals, present in smaller but important amounts (the image shows the percentages for humans). Approximately 2/3 of the existing periodic table is composed of metals with varying properties, accounting for the diverse ways in which metals (usually in ionic form) have been utilized in nature and medicine.
  • 2.0K
  • 10 Oct 2022
Topic Review
Laser Dynamic Compression in Diamond Anvil Cells
The field of high-pressure materials research has grown steadily, with many remarkable discoveries having been made. Recent progress in laser material processing within diamond anvil cells (L-DACs); researchers focus on the practice of laser-driven dynamic compression within diamond anvil cells (i.e., LDC–DAC experimentation).
  • 2.0K
  • 28 Nov 2022
Topic Review
Stone Cultural Heritage Elements
Stones are ones of the most ancient natural materials exploited by humans, with different uses, from tools to buildings, that have endured over time in better conditions than other objects belonging to cultural heritage. Given the importance of those silent witnesses of the past, as well as our duty to preserve all parts of cultural heritage for future generations, much effort was put into the development of materials for their consolidation, protection, self-cleaning, or restoration.
  • 1.9K
  • 20 Sep 2022
Topic Review
Aurivillius-Phase Bi4Ti3O12-nBiFeO3 Materials
Aurivillius-type layered compound have attracted increasing research interest, especially in recent 20 years, due to their promising electrical properties as new lead-free piezoelectric materials operating at high temperatures. For instance, the well-known Bi4Ti3O12, presents large spontaneous polarization, anisotropy and high ferroelectric Curie temperature and have wide applications in the electronic industry, capacitors, transducers, nonvolatile ferroelectric memories, piezoelectric sensors and optical devices. To increase functionality of Bi4Ti3O12 modification with BiFeO3 is very promising, which is also a methodology for constructing single-phase multiferroics in which ferrelectricity and magnetic ordering are coupled near room temperature. Combining these two materials exhibiting different physical performances one can create a kind of novel materials and thus achieve functionality. Herein, we summarized the recent progress in the field of synthesis of BFTO-n materials with various architectures and highlighted their extraordinary properties for promising applications in the electronic industry, quantum devices, capacitors, transducers, microwave absorbers, catalysts and photoelectric devices. 
  • 1.9K
  • 13 Jan 2021
Topic Review
Detect Defects by Deep Learning
The detection of product defects is essential in quality control in manufacturing. This study surveys stateoftheart deep-learning methods in defect detection. First, we classify the defects of products, such as electronic components, pipes, welded parts, and textile materials, into categories. Second, recent mainstream techniques and deep-learning methods for defects are reviewed with their characteristics, strengths, and shortcomings described. Third, we summarize and analyze the application of ultrasonic testing, filtering, deep learning, machine vision, and other technologies used for defect detection, by focusing on three aspects, namely method and experimental results. To further understand the difficulties in the field of defect detection, we investigate the functions and characteristics of existing equipment used for defect detection. The core ideas and codes of studies related to high precision, high positioning, rapid detection, small object, complex background, occluded object detection and object association, are summarized. Lastly, we outline the current achievements and limitations of the existing methods, along with the current research challenges, to assist the research community on defect detection in setting a further agenda for future studies.
  • 1.9K
  • 28 Sep 2021
Topic Review
Nanocellulose Hybrids with Magnetic Nanoparticles
Cellulose is one of the most affordable, sustainable and renewable resources, and has attracted much attention especially in the form of nanocellulose. Bacterial cellulose, cellulose nanocrystals or nanofibers may serve as a polymer support to enhance the effectiveness of metal nanoparticles. The resultant hybrids are valuable materials for biomedical applications due to the novel optical, electronic, magnetic and antibacterial properties. In particular, superparamagnetic iron oxides nanoparticles with very small size (SPIONs) are non-toxic in small concentration, biodegradable and biocompatible and display a high magnetic resonance imaging (MRI) contrast effect. However, for biomedical applications, SPIONs need to be covered by a biocompatible shell to prevent aggregation or degradation and to delay the immune response. Nanocellulose proved to be an excellent biocompatible matrix for SPIONs in MRI applications.
  • 1.9K
  • 08 Sep 2020
Topic Review
Self-Assembled III-V Semiconductor Quantum Dots
A fundamental understanding of the growth of semiconductors is essential for the optimization of quantum dot-based optoelectronic devices. Droplet epitaxy has proven to be the successful versatile growth method for instance growing quantum dots with a small fine structure splitting for quantum information technology. Precise control and tuning of the quantum dots for various applications is only possible through a detailed understanding of the growth mechanism at the atomic level, which creates the need for atomic-scale structural and composition characterization. We present an overview of the results of detailed structural and composition analysis by cross-sectional scanning tunneling microscopy and atom probe tomography of quantum dots grown by self-assembled droplet epitaxy where we focus mainly on strain-free GaAs/AlGaAs and strained InAs/InP QDs.
  • 1.9K
  • 19 Jan 2021
Topic Review
Features of Clay Minerals Supporting Carbon Dioxide Capture
Carbon capture is among the most sustainable strategies to limit carbon dioxide emissions, which account for a large share of human impact on climate change and ecosystem destruction. This growing threat calls for novel solutions to reduce emissions on an industrial level. Carbon capture by amorphous solids is among the most reasonable options as it requires less energy when compared to other techniques and has comparatively lower development and maintenance costs. In this respect, the method of carbon dioxide adsorption by solids can be used in the long-term and on an industrial scale. Furthermore, certain sorbents are reusable, which makes their use for carbon capture economically justified and acquisition of natural resources full and sustainable. Clay minerals, which are a universally available and versatile material, are amidst such sorbents. These materials are capable of interlayer and surface adsorption of carbon dioxide.
  • 1.9K
  • 13 Apr 2022
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