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In this study, we examined the frequently reported "selective fluorescence quenching effects" of Fe3+ ions on carbon dots. Instead of the believed "quenching effects" by Fe3+, the strong reduction of the fluorescence of carbon dots is likely because of the inner filter effect, which is caused by the strong ultraviolet (UV) absorption of Fe3+. With the addition of Fe3+ ions, the UV absorption increases dramatically, compared to other metal ions. When Fe3+ ions coexist with carbon dots (CDs) in the solution, most of the excitation light is absorbed by Fe3+ ions, decreasing the excitation light obtained by CDs. This phenomenon leads to the "fluorescence quenching." This finding helps us gain a better understanding of the fluorescence quenching effects of metal ions on carbon dots and understand the quenching effect of metal ions on other fluorescent materials. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) are coordination networks consisting of a metal ion linked with organic ligands. The resulting three-dimensional structures create pores that can be exploited for a number of chemical processes, including analytical extractions. The resulting sorbent-based extraction systems have several advantages, notably selectivity. The use of MOF in extraction has exploded in the last two or three years. In this article, we take a look at the current state of the art regarding analytical extractions utilizing MOF, including a description of what MOF are, their preparation, principles of use, advantages, and application areas. [ABSTRACT FROM AUTHOR]

The article discusses the role of qualifier ions in inductively coupled plasma-mass spectrometry (ICP-MS). It notes that the first row transition elements between scandium and selenium are affected by the most common spectroscopic interferences in ICP-MS. It explores approches to qualifier ion confirmations such as the calibration and quantification of both isotopes and comparing the quantitative results.

Presents speciation studies of metal ions in environmental and biological media using supported liquid membrane extraction. Extraction of the bioavailable fraction; Extraction of the bioavailable and chemical form; Extraction achieved by incorporating a carrier in a membrane that selectively extracts the bioavailable form of the metal ion; Miniaturized liquid-membrane extraction designs suited for speciation studies of metal ions in small amounts of biological fluids.

Focuses on the mechanisms of electrolytic deposition. Role of metal ion hydrolysis in achieving cathodic electrolytic deposition; Use of thermal treatment in converting hydroxide and peroxide deposits to corresponding oxides; Occurrence of anodic reaction during electrolytic deposition.

The article focuses on the development of carboxylates by reacting carboxylic acids with strong bases, such as inorganic hydroxides. It discusses the use of the resultant salts as cleansers, explores the infrared peals from the carbon-oxygen bond and linkages that coordinate with metal ion, and looks at the synthesis of acid anhydrides. The reaction of carboxylic acid with sodium hydroxide is illustrated.

The article reports that Metal-organic framework (MOF) compounds belonging to porouscrystalline materials that are composed of metal ions joined by organic linkers. Liquid versions of these materials are useful because liquids tend to be more robust and easier to process. The team led by Thomas D. Bennett François-Xavier Coudert have succeeded in making a liquid version of a MOF.

The article reports on a research study by Bo Li and colleagues at the University of North Carolina, Chapel Hill, where they found that a dithiolopyrrolone (DTP) called holomycin exerts its antibiotic activity by sequestering intracellular metal ions. This metal chelation activity was found to inhibit some metalloenzymes and disrupt cells' internal metal balance.

The article presents a study conducted by researchers Mato Knez and Seung-Mo Lee and colleagues which found that β-sheet crystals in the silk proteins decreases in size when metal ions bond to amino acids in the fibers, published in a 2014 issue of the journal "Applied Materials & Interfaces." It mentions that smaller metalized crystals dissipate energy when the fibers are attached because they can respond to shear forces cooperatively and more uniformly than larger ones.

The article discusses deburring, a process wherein the transfer of metal ions are occurring rapidly on corners or edges of metal parts and when properly controlled, removes burrs form complex or fragile parts that do not lend to conventional tumbling or vibratory finishing techniques.

Reports the methodology employing high-efficiency liquid ion exchange for the recovery, separation and concentration of heavy metals. Discussion on the summary of procedures; Advantages associated with the technology; Future applications of the technology on soil remediation, acid mine drainage and recycling of spent nuclear waste.

Reports on the technique for detecting mobile metal ions (MMI). Potential of the MMI technology in finding minerals that are buried by deep soil cover; Use of machines such as inductively coupled plasma mass spectrometers.

Presents information on the use of chemicals to act as chaperone protects in the transportation of metal ions. Details on how this works; Identification of the chemicals involved; Reference to the researcher involved in the study; How copper moves.

The article discusses research study on the role of metal ions in protein assembly. It references a study by F. Akif Tezcan and colleagues, published in "Nature Chemistry." Study authors concluded that using zinc ions to produce proteins could make it possible to design and create polymers with protein-based functions and properties for nanotechnology use. INSETS: METAL-BASED ASSEMBLY;TOTALLY TUBULAR.

The article reports on the artificial enzyme created by a research team from the University of Michigan in Ann Arbor. The enzyme is comprised of three helices and two different metal ions and has the ability to catalyze reactions near the same level of efficiency as those of natural enzymes. It has been considered as a major breakthrough in protein design, despite the fact that the synthetic enzyme's activity only equals around 0.01 percent of natural oxidases.

The article presents a response from Abdul-Mujeed Azad, Desikan Sundararajan, Sirhan Al-Batty and Eric McDaniel regarding the critiques of Department of Materials Engineering investigators K. T. Jacob and R. Adharsh in India on carbon dioxide (CO2) utilization. They mention the kinetic limitations of their proposal since iron oxide and metallic iron are consumables and not catalysts. They further stresses the credibility of their data based on research studies.

The article describes a family of self-healing metallosupramolecular polymers from a group led by Stuart Rowan of Case Western Reserve University and Christoph Weder of the University of Fribourg, in Switzerland. It notes that the material is based on short polymer chains that terminate in a ligand that can coordinate to a metal ion. The material's significance for spot-repairing damage to coatings, paints, and polymer thin films is also cited.

The article reports on the use of fourier transform infrared technology (FT-IR) by researchers São State University in Ilha Solteira, Brazil to examine the use of minced banana peel to extract lead and copper ions from water.

The article deals with the lengthening of the metal organic framework (MOF) compounds. These compounds refer to crystalline materials made of metal ions or clusters that are linked by organic linkers. A study conducted by Omar M. Yaghi and colleagues found that the compounds can be synthesized through the lengthening of the organic linkers in previous record setters and by applying combinations of organic linkers. Another study found that the compounds undergo a paraelectric-ferroelectric transition.

The article reports on a way of simultaneously detecting and removing heavy metal ions using a hydrogel that shrinks as it absorbs pollutants developed by researchers at the University of California in Berkeley. Led by chemistry professor Matt Francis, the researchers combined a series of metallothionein proteins with a polymer substrate. The researchers believe that the discovery offers a low-cost detection method for heavy metals, especially for developing countries.

The article focuses on the study regarding the capability of enzymes to select right metal ion. Studies show that cells can ensure the enzyme picks the right metal ion by controlling which cellular compartment the protein is folding in. Cells know and can easily locate the right metal in the protein by controlling the position of nascent protein folds. Only the manganese-containing protein is allowed to fold in, since manganese has trace metals that are important for the function of enzymes.

The article reports that chemical engineer researchers from the University of Grenada in Spain have discovered that olive stones can be applied to the extraction of water-dissolved metals. Germán Tenorio Rivas has found that through the process of biosorption, olive stones will extract chromium ions from the wastewater produced by the paint, tannery and galvanising industries.

The article cites key research findings from Frankfurt, Germany in 2007 indicating that peptide-based tags than bind two lanthanide ions can be created and easily added to proteins. The research shows the applications of lanthanide metal ions in increasing the power of spectroscopy in the study of proteins.

The article features DigiSEP solid-phase extraction cartridges. These products help to capture, collect and concentrate certain elements in complex matrices. It collects metal ions from acid digestion matrices. Further, it helps separate heavy metals from oil and other organic matrices. Specific lead and mercury cartridges are offered.

The article demonstrates the examples of the first f-f electron coupling for lanthanide-actinide complexes by researchers at the Los Alamos National Laboratory. The team synthesized the complexes by coupling thorium or uranium ketimide-terpyridine complexes to an yterbocene complex. The uranium complex is one of only three known structurally characterized complexes containing both lanthanide and actinide metal ions.

Discusses a study that lends support for magnesium ion having a flexible inner coordination sphere. Key to the action of metallohydrolases; Finding that magnesium ion can replace zinc ion; Implication for magnesium chemistry in biological systems.

Reports that a crystal structure of a portion of RNA offers insights to researchers in the United States about the workings of self-splicing group I intron. Replacement of four RNA nucleotides with their DNA analogs; Structural evidence for two metal ions associated with the active site; Protein synthesis.

Presents news updates on chemistry as of August 4, 2003. Crystal structure of an RNA aptamer with the transcription factor nuclear factor-kappaB; Use of metal ions to induce trans-cis isomerization.