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The article discusses the impact of Hurricane Helene on the semiconductor industry in North Carolina. Two primary mining companies that produce high-quality quartz used in the production of semiconductors were forced to shut down due to the hurricane. One of the plants has reopened, while the status of the other remains unknown. The companies are working to assess the damage and restore production as soon as possible. The article highlights the importance of these mining operations for the local economy and the challenges faced by the computer chip industry in increasing production. [Extracted from the article]

The article focuses on the final rule issued by the Mine Safety and Health Administration (MSHA) to better protect miners from health hazards associated with exposure to respirable crystalline silica. It highlights the key provisions of the final rule, including the lower permissible exposure limit, requirements for mine operators to use engineering controls and establish medical surveillance programs, and the replacement of outdated standards for respiratory protection.

The article focuses on specialty materials company, PPG Industries Inc. planning to sell its precipitated silica products business to Qemetica SA, a privately-held producer based in Warsaw, Poland.

The article reports that U.S. Silica Holdings Inc.'s shareholders approved its acquisition by Apollo Global Management Inc. Topics discussed include the approval of the merger at a special meeting, the expected closing timeline subject to agreement terms, and U.S. Silica's role as a leading producer of silica for industrial applications and logistics.

The article discusses the potential of various packaging materials for Silicon Carbide (SiC) sensors at high temperatures. Topics discussed include the investigation of ceramic and glass materials to replace aluminum nitride, which is currently used to package SiC-based electronics, but has limitations at temperatures above 800°C, and the testing of four ceramics and silicon dioxide glass to determine their resistivity and stability at high temperatures. [ABSTRACT FROM PUBLISHER]

In a previous study, polyphyllin III, an important natural dioscin ingredient, was bonded to silica particles using the "one-pot method" for preparing a stationary phase, called SP-D. SP-D was further modified to produce two stationary phases, namely the phenyl isocyanate-dioscin (Phe-D) and 3,5-dimethyl phenyl isocyanate-dioscin bonded silica stationary phase (DMP-D), respectively. The Phe-D and DMP-D were evaluated by achiral and chiral analytes. The high performance liquid chromatography (HPLC) method was optimized and applied to the analysis of the main active ingredient, polyphyllins, that were contained in gongxuening capsules, a traditional Chinese medicine (TCM) widely used to treat gynecological diseases. The two synthesized stationary phases were also applied to the separation of the amino acid (AA) enantiomers. For this study, 10 a-AAs (lysine, leucine, cysteine, arginine, isoleucine, threonine, serine, valine, alanine, and histidine) were selected and studied for chiral separation using Phe-D and DMP-D stationary phases. In this study, 10 observed AA enantiomers were separated to different degrees on at least one stationary phase whereas four AAs were enantioseparated on both Phe-D and DMP-D. These results indicated that the two synthesized stationary phases have potential applicability in quality control (QC) of TCM and chiral separation as well as offering a new application choice for analyses of natural products. [ABSTRACT FROM AUTHOR]

The article discusses the U.S. Department of Labor's proposed rule change through its Mine Safety and Health Administration (MSHA) to enhance protections against respirable crystalline silica exposure for miners. Topics include the proposed rule's impact on miners' health, industry responses from organizations like the National Stone, Sand & Gravel Association, and MSHA's ongoing efforts to conduct impact inspections and enforce safety regulations in mines.

The article reports that PPG Industries Inc. is exploring strategic options for its silica products business, accounting for 1%-2% of its annual sales, with plans to conclude the review by mid-2024. PPG has hired Morgan Stanley & Co. LLC as a financial advisor for the assessment, considering potential divestiture or spin-off due to the business's unique characteristics and market positi.

The article focuses on Ecovyst's expansion and rebranding of its advanced silicas product portfolio, consolidating functional silica and silica-based catalyst lines under a new advanced silica segment, driven by the company's commitment to enhancing the performance and sustainability of products.

The article focuses on the U.S. Mine Safety and Health Administration's (MSHA) proposed new silica rule, aiming to lower miners exposure to respirable crystalline silica. Topics discussed include MSHA's intention to set a permissible exposure limit (PEL) for silica, various requirements and controls in the proposed rule, and the need for public comments before finalization.

The article centers on the U.S. Department of Labor's Mine Safety and Health Administration (MSHA) proposed amendment to better protect miners from health hazards related to respirable crystalline silica exposure, including severe health issues.

The article discusses about the forthcoming rule to establish an updated respirable crystalline silica standard by the U.S. Mine Safety and Health Administration (MSHA). Topics discussed include the current status of a new silica standard, barriers to releasing a timely proposal and anticipated timeline for the promulgation of a new silica standard.

The article focuses on the use of real-time respirable dust monitors to address the silica health hazard in mining. Topics cited include the difference between an average concentration detected by the real-time monitor and the true concentration value as determined from a gravimetric sample, a study by the National Institute for Occupational Safety and Health on the performance of light scattering monitors, and calibration of real-time dust monitors at the factory via a standardized test dust.

The article focuses on the U.S. Department of Labor's proposal to amend federal standards for miners protection against health hazards related to silica dust exposure. Topics discussed include the proposed rule change, maintaining permissible exposure limits, and the impact on mining companies already following the U.S. Occupational Safety and Health Administration's (OSHA's) silica rule.

The article discusses the use of sintered stone as the material for building facades. Topics discussed include the high strength and durability of sintered stone, the steps for manufacturing sintered stone which include the pressing of raw materials and firing, and natural ingredients in sintered stone including granite materials, silica and glass minerals, clay minerals and natural pigments.

The article discusses the announcement of a Silica Enforcement Initiative aimed at increasing silica-related enforcement at UMWA's 56th Constitutional Convention in June 2022 by the Mine Safety and Health Administration (MSHA). MSHA's Silica Enforcement Initiative has four components, including inspections, sampling, compliance assistance, and miners' rights.

El artículo discurre sobre la silice en la nutrición vegetal. El autor comenta sobre la prevalencia de la silice en la naturaleza, incluyendo en los suelos y los microorganismos. También se examinan los estudios sobre la silice desde el siglo 19 y se consideran las interacciones entre la silice y otros elementos.

The article focuses on the discovery made by an international team of physicists and materials scientists from Bayerisches Geoinstitut, Linkoping University, and the California Institute of Technology regarding an impossible modification of silica-coesite-IV and coasite-V materials.

The article discusses how hollow silica particles could form the basis of next-generation thermal insulation systems. It states that hollow silica particles have low thermal conductivities and can be synthesized by several low-cost strategies. It also mentions that researchers at Oak Ridge National Laboratory freeze-dried a mixture of hollow silica particles with cellulose fibers and carbon black to create a hydrophobic and structurally stable composite.

The article reports that the U.S. Department of Labor's Mine Safety and Health Administration has launched an enforcement initiative to protect the nation's miners from health hazards from repeated overexposure to respirable crystalline silica.

The article describes developments in the preparation of organic polymer monoliths suitable for the separation of small molecules in the isocratic mode. Topics discussed include adjusting the polymerization mixture composition, effect of polymerization temperature on column efficiency, and post-polymerization surface modifications. The difference between silica-based and organic polymer monoliths in their pore morphology is mentioned.

The article discusses a technique related to high performance liquid chromatography (HPLC) for demonstrating a quantum leap in protein column efficiency. It informs that using colloidal silica particles plate heights of chromatography column can be reduced to Hagen-Poiseuille flow. This technique is also called slip flow.

The article highlights the state of the ceramics industry in India, which research efforts are more focused on traditional applications like whitewares and structural ceramics. Indian Ceramics Society president A. L. Shashi Mohan said the country is currently focused on improving its infrastructures so their emphasis is more on bulk refractory products like silica, aluminosilicates and alumina among others. The industry's growth is expected to continue in 2013. INSET: From emerging market to economic powerhouse.

The article offers information on the new generation fully porous core shell particles which are used as column packing materials due to significant improvements in their physicochemical parameters. It mentions the physicochemical parameters which include surface roughness, particle size distribution and the robustness of the base core-shell silica. It further informs that the fully porous particles promote better heat conductivity.

With the advent of the second generation of commercial silica monolith columns, liquid chromatographers now have an alternative to the sub-2-um and core-shell packings for high-throughput, high efficiency separations. In this article, the preparation of the new-generation silica-based monolithic high performance liquid chromatography columns is described in detail and the first- and second-generation columns are compared based on physical characteristics, with application examples given. The future prospects for silica-based monoliths also are explored. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the conformational order, packing, and phase transition behavior of supported lipid bilayers (SLBs) of zwitterionic lipids on silica nanoparticles using the Raman spectroscopy. The study indicates that the lipids' lateral packing, as well as the relative number of trans conformers increased as the size of the nanoparticle decreased. It infers that Raman spectroscopy is a powerful technique in studying the interface region of inorganic nanoparticles.

The article presents a study which uses core-shell silica particles to allow fast and accurate high performance liquid chromatography (HPLC) analysis of vitamin D levels in patient's serum samples. Protein precipitation is utilized for sample preparation of the serum samples to interfere with the protein serum association 25-OH D2 and 25-OH D3. The study offers the most significant breakthrough on the HPLC analysis, improving its resolution and effectiveness rendered by the core-shell column.

The realization that supercritical fluid chromatography (SFC) is now viewed as modern normal-phase liquid chromatography has prompted a reexamination of bare silica as a viable stationary phase for packed- column SFC. Published documents that appeared before and after 2000 involving bare silica and carbon dioxide-methanol mobile phases are reviewed. A current study that experimentally compares five bonded phases with bare silica for the SFC separation of a 19-component mixture of polar analytes is reported. [ABSTRACT FROM AUTHOR]

The article offers information on chemical firms that aim to enhance environmental performance of tires through their innovations without reducing safety and durability. It states that proper tire inflation can save more energy quickly in a low cost but can not deliver the energy volume that offshore drilling does. It adds that chemical firms use new forms of silica and nanomaterials in optimizing the rolling resistance of tires while maintaining other functions that tires need to deliver.

The article discusses the low-defect germanium (Ge) and gallium arsenide (GaAs) materials in silicon dioxide trenches on silicon through aspect ratio trapping (ART) method. It shows that GaAs/InGaAs quantum well lasers can be formed on silicon substrates using ART method and chemical mechanical polishing with a misfit-defect reducible by enhancing epitaxial lateral overgrowth (ELO) process. Moreover, it notes that a 22 percent of differential quantum efficiency is obtained without facet coating.

The article compares the abilities of silica-based solid-phase extraction (SPE) and polymer-based SPE. The author explains that silica-based sorbents can be applied to any SPE problem, but they have a limited pH range and have the presence of residual silanol groups. Polymeric sorbents, on the other hand, promise a wide pH range and their ability to tolerate solvents and buffers that would harm or destryo a silica-based sorbent.

The article discusses the impact of flow-rate adjustment and system suitability on liquid chromatography (LC) separation. The variable that could possibly affect LC retention times are listed including variations in the mobile phase composition, column chemistry and column temperature. It is noted that chemistry changes between columns are less common with high-purity silica columns compared with lower-purity columns. Tips if the problem on shorter retention times is encountered are presented.

The article focuses on a 1987 survey conducted on technology experts regarding the future of high performance liquid chromatography (LC). Results of the survey were compared with the current chromatographic technology two decades later. Several correct predictions made include the use of LC in the preparative-and process-scale, need of biotechnology to bring more biocompatible columns and use of silica-based columns. Key information about the wrong predictions made is presented.

The article provides an overview of gas chromatography (GC) columns and dicusses how fused-silica capillary GC column could be constructed in the production setting to emphasize its efficient usage. It presents various classifications of GC in relation with their uses, including packed-column GC, open-tubular columns and capillary columns. Meanwhile, information on the twelve individual steps in the production of fused-silica capillary column are offered.

The article investigates the optical properties and thickness of natural silicon dioxide thin films grown in silicon substrates with a variable spectroscopic ellipsometry. By selecting the various angle of incidence and wavelength ranges, the properties and thickness of silicon dioxide film are studied. The result indicates that the refractive index of silicon dioxide is static in value.

The article describes a method for retaining polar and nonpolar compounds on the same high performance liquid chromatography stationary phase with an isocratic mobile phase. Hydride silica-based stationary phases are materials with properties that allow for the simultaneous retention of polar and nonpolar compounds over a range of aqueous-organic mobile phase compositions.

Features products for the chromatography sector in the United States. Horizon's DryVap automated concentrator system; Phenomenex Inc.'s Gemini C18 silica; Marvel Scientific's chromatography refrigerators; Waters' Empower 2 chromatography data management software.

Describes the production and installation of fused-silica capillary gas chromatography (GC) columns. Developments in fused-silica column technology; Distinctions between the common and modern fused-silica; Material properties of capillary fused-silica tubes.

The article reports that peak tailing is nearly ubiquitous for peaks in liquid chromatography separations. The high-purity silica used by most vendors of reversed phase columns greatly reduces tailing when compared with materials used in earlier generations of column packings. If the column is overloaded with sample, any peak can exhibit tailing as well. In still other cases, a small peak eluted on the hack edge of a larger peak sometimes can masquerade as a peak tail rather than a separate peak.

Silica litigation has all the characteristics of a true mass tort and many similarities to asbestos litigation. Insurance underwriters and producers in particular and the industry in general should be familiar with the general background and drivers behind the growth in this area to effectively deal with risks presenting exposure to casualty lines of business. [ABSTRACT FROM AUTHOR]

Reports that Praxair Inc. and Heye Glass have successfully developed the first tall crown furnace (TCF) vanced oxy-fuel-fired glassmelting. Decrease in silica refractory corrosion and nitrogen oxide, sulphur oxide and particulate emissions while maintaining the high heat transfer and energy efficiency of traditional oxy-fuel-fired glassmelting technology; Key TCF design features; TCF design goals; Effects of burner elevation.

Hydrophilic interaction chromatography (HILIC) is a useful technique for the retention of polar analytes that offers a difference in selectivity compared to traditional reversed-phase chromatography. This paper examines the use of a silica column for HILIC, including mechanistic studies of analyte retention on silica in aqueous-organic mobile phases. The authors compare a silica column and C18 column to demonstrate the increased sensitivity of using HILIC with electrospray ionization mass spectrometry (ESI-MS). They also report a quantitative LC--MS method for the analysis of acetykholine, choline, and choline-trimethyl-d9, and describe a simplified solid-phase extraction (SPE) procedure that allows the direct injection of extracted organic fractions from SPE devices onto a silica column. [ABSTRACT FROM AUTHOR]

Discusses the implementation of a silica risk-control strategy. Background on a decline in the number of silica-related mortality in the U.S. in 2000; Role of government regulations in the prevalence of silica-related litigations; Significance of auditing material safety data sheets in dealing with potential silica-related litigations.

Hydrophilic interaction chromatography (HILIC) is a useful technique for the retention of polar analytes that offers a difference in selectivity compared to traditional reversed-phase chromatography. This paper examines the use of a silica column for HILIC, including mechanistic studies of analyte retention on silica in aqueous-organic mobile phases. The authors compare a silica column and C18 column to demonstrate the increased sensitivity of using HILIC with electrospray ionization mass spectrometry (ESI-MS). They also report a quantitative LC-MS method for the analysis of acetylcholine, choline, and choline-trimethyl-d9, and describe a simplified solid-phase extraction (SPE) procedure that allows the direct injection of extracted organic fractions from SPE devices onto a silica column. [ABSTRACT FROM AUTHOR]

Discusses the treatment for scale, a mixture of soluble mineral salts and deposit-related problems of open recirculating cooling water systems of power plants. Information on chemical water treatment techniques to avoid releases of deposition and scale; Details of the silica scale formation with cooling water; Prevention of the formation of silica scale; Factors to consider in choosing a chemical treatment program process.

Studies the use of kaolin, metakaolin and microsilica as fillers for alumina-based refractory castables. Functions of fillers; Properties of fillers; Preparation of castables; Flow behavior of castables; Mullite formation in castables.

Focuses on the use of molsieves and silica gel in a process gas stream. Inclusion of pressurization and depressurization in the cooling and heating phases; Measurement of raw and purified air moisture with a portable dew point meter; Accumulation of water during standstill conditions.

Presents an efficient and informed approach to silica-based high performance liquid chromatography (HPLC) column selection based upon complementary decisions on bonded-phase and particle characteristics. Details on the column selection approach; Factor that influenced the choice of a column's particle physical characteristics; Procedure in choosing the bonded phase; Assessment of the role of base silica chemistry.

Examines the effects of active silica on the slip properties of sanitaryware. Synthesis of ultrafine powders; Applications of active silica; Characteristic of slip properties.