chemical

The university chemical dependency project : final report : November 1 1986 / Steven A. Bloch, Steven Ungerleider.

[Indiana] : Integrated Research Services, Inc., 1986.




chemical

Functional and preservative properties of phytochemicals

9780128196861 (electronic bk.)




chemical

Official disputes EPA toxic chemical release analysis




chemical

Biochemical Characteristics and Risk Factors for Insulin Resistance at Different Levels of Obesity

Although the metabolic syndrome is associated with obesity, not all obese children have insulin resistance and metabolic syndrome, and nonobese children may develop these abnormalities. Associated factors have not been well described.

There was a 6.6% prevalence of nonobese children who were insulin-resistant, associated with a family history of hypertension. There was a 21.3% prevalence of obese who were not insulin-resistant, associated with a low waist circumference. (Read the full article)




chemical

Biochemical Characterization of QPX7728, a New Ultra-Broad-Spectrum Beta-lactamase Inhibitor of Serine and Metallo-Beta-Lactamases [Mechanisms of Resistance]

QPX7728 is a new ultra-broad-spectrum inhibitor of serine and metallo beta-lactamases from a class of cyclic boronates that gave rise to vaborbactam. The spectrum and mechanism of beta-lactamase inhibition by QPX7728 were assessed using purified enzymes from all molecular classes. QPX7728 inhibits class A ESBLs (IC50 range 1-3 nM) and carbapenemases such as KPC (IC50 2.9±0.4 nM) as well as class C P99 (IC50 of 22±8 nM) with a potency that is comparable or higher than recently FDA approved BLIs avibactam, relebactam and vaborbactam. Unlike those other BLIs, QPX7728 is also a potent inhibitor of class D carbapenemases such as OXA-48 from Enterobacteriaceae and OXA enzymes from A. baumannii (OXA-23/24/58, IC50 range 1-2 nM) as well as MBLs such as NDM-1 (IC50 55±25 nM), VIM-1 (IC50 14±4 nM) and IMP-1 (IC50 610±70 nM). Inhibition of serine enzymes by QPX7728 is associated with progressive inactivation with a high efficiency k2/K ranging from of 6.3 x 104 (for P99) to 9.9 x 105 M-1 s-1 (for OXA-23). This inhibition is reversible with variable stability of the QPX7728-beta-lactamase complexes with target residence time ranging from minutes to several hours: 5-20 minutes for OXA carbapenemases from A. baumanii, ~50 minutes for OXA-48 and 2-3 hours for KPC and CTX-M-15. QPX7728 inhibited all tested serine enzymes at 1:1 molar ratio. Metallo-beta-lactamases NDM, VIM, and IMP were inhibited by a competitive mechanism with fast-on-fast-off kinetics, with Kis of 7.5±2.1 nM, 32±14 nM and 240±30 nM for VIM-1, NDM-1 and IMP-1, respectively. QPX7728 ultra-broad-spectrum of BLI inhibition combined with its high potency enables combinations with multiple different beta-lactam antibiotics.




chemical

Secretary of State Announces Chemical Dependency Counselor License Suspension

Secretary of State Jeffrey Bullock has suspended the Delaware chemical dependency counseling license of Sachin Karnik in light of recent criminal charges filed against him.



  • Department of State
  • "Secretary of State"
  • chemical dependency counseling
  • Division of Professional Regulation
  • Professional License

chemical

Chennai Pharmacist Dies After Drinking Chemical He Made To Treat COVID-19

A pharmacist died and his boss was left hospitalised after the pair drank a chemical concoction they had developed in an effort to treat coronavirus, police said Saturday. The men worked for a herbal...




chemical

USAF, Dover AFB advise state agencies that PFAS chemicals exceeding EPA health advisory found in four wells near base

The US Air Force and Dover Air Force Base have notified Delaware’s Department of Natural Resources and Environmental Control and Division of Public Health, that four wells near the base sampled by the federal government for perfluoroalkyl substances (PFAS), including perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), have returned elevated levels of PFOS and PFOA above the US Environmental Protection Agency’s health advisory for these substances of 70 parts per trillion (ppt).



  • Delaware Health and Social Services
  • Department of Natural Resources and Environmental Control
  • Division of Public Health
  • Division of Waste and Hazardous Substances
  • Office of the Governor
  • Dover Air Force Base
  • health advisory
  • perfluoroalkyl substances (PFAS)
  • perfluorooctane sulfonate (PFOS)
  • perfluorooctanoic acid (PFOA)
  • US Air Force
  • US Environmental Protection Agency
  • waste and hazardous substances

chemical

Amid Protest, Chemical Firm Sorry For Leak That Killed 11 At Andhra Plant

The Indian arm of a South Korean chemical major has apologised after a gas leak at its plant in Andhra Pradesh killed 11 and affected at least a thousand people. A tank used to store chemicals for...




chemical

NGOs set targets for new EU chemicals strategy

Commission must safeguard standards in the wake of Covid-19




chemical

China publishes final text of regulation governing new chemicals

MEE Order 12 comes into force 1 January 2021




chemical

Church and Dwight eliminates 97% of ‘chemicals of concern’

Consumer products giant provides updates on 2020 chemicals goals




chemical

Envi urges ‘dynamic alignment’ of future UK-EU chemicals laws

Pushes need for future cooperation agreements




chemical

Whirlpool deploys chemicals management tool across EMEA region

Covid-19 causing disruptions but compliance a 'critical pathway'




chemical

Nordic Council: keep ambition high on post-2020 chemicals framework

'Necessary' for sustainable recovery after Covid-19 pandemic




chemical

Villagers Hit By Vizag Gas Leak Can't Return Till Chemical Neutralised

The Andhra Pradesh government has today informed that those evacuated from villages affected by the gas leak from a chemical plant in Visakhapatnam could not return till the impact of the chemical was...




chemical

India's chemical plant disaster: another case of history repeating itself

Decades after Bhopal, lack of law enforcement and political will plagues Indian industry

The gas leak at a chemical factory in Visakhapatnam will immediately remind many in India and beyond of the 1984 Bhopal disaster, widely considered the world’s worst industrial disaster.

So far, the scale of the tragedies are very different. Eleven people are confirmed to have died in Visakhapatnam – but with hundreds hospitalised and thousands affected, there are fears the toll will rise. In Bhopal, 4,000 people died within days of the toxic gas leak from a pesticide plant in the central Indian city, and thousands more in the following years.

Continue reading...




chemical

Hundreds exposed to gas after deadly leak at Indian chemical factory

Gas from LG Polymers plant in Andhra Pradesh leaked into nearby homes while families slept

At least 11 people have been killed and hundreds more taken to hospital after a gas leak at a chemical factory in south-east India.

A plastics plant owned by South Korea’s LG Corp started leaking styrene into the surrounding residential area at about 3am on Thursday. Some people were enveloped as they slept, while others collapsed in the streets as they tried to flee the area on the outskirts of the coastal city of Visakhapatnam.

Related: 'Bhopal’s tragedy has not stopped': the urban disaster still claiming lives 35 years on

Continue reading...




chemical

India chemical leak: more evacuations amid fears of second gas release

Everyone within 5km of the plant in Andhra Pradesh told to leave over fear of repeat of accident that has left at least 11 dead

Indian officials have evacuated more people from the area around a chemical plant in the south of the country that leaked toxic gas, killing at least 11 people and sickening hundreds more.

There was confusion about whether the wider evacuation orders were sparked by a renewed leak at the LG Chem factory in Andhra Pradesh, or by the fear that rising temperatures at the plant could lead to another leak.

Related: India's chemical plant disaster: another case of history repeating itself

Related: 'Bhopal’s tragedy has not stopped': the urban disaster still claiming lives 35 years on

Continue reading...




chemical

Sumitomo Chemical to buy Botanical Resources Australia

Japanese chemical giant Sumitomo Chemical group has spent approximately ¥15 billion (A$177 million) on Botanical Resources Australia, a Tasmanian pyrethrum business.




chemical

Hanwha Chemical an Unexpected Beneficiary of Coal Price Hike

As international coal prices are on the rise, Hanwha Chemical's prospect is getting brighter. That's because the Korean company uses naphtha to produce polyvinyl chloride (PVC) while its rivals in China are largely based on coal, which will make it more price competitive vis-a-vis the Chinese chemical producers. According to Korea Resources Corp. and chemical industry sources on September 10, the freight-on-board (FOB) price of bituminous coal out of the Chinese port of Qinhuangdao was US$95....




chemical

Considering the impact of the proposed Brexit deal on Chemicals Regulation at the House of Commons

On 4 December 2018, Eversheds Sutherland’s Elizabeth Shepherd was on a panel providing oral evidence to the House of Commons Environmental Audit Committee at a one-off session to consider the impact of the proposed Brexit deal on Chemicals Reg...




chemical

Inquiry launched to investigate the impact of toxic chemicals in everyday products

The Environmental Audit Committee (“EAC”) has launched an inquiry to investigate the impact of toxic chemicals on everyday life (launched 12 February 2019). The inquiry will focus on the use of toxic chemicals in everyday products includ...




chemical

Chemical Regulation – the Outlook for 2020

The below summarises some of the key chemical’s regulation related changes expected in 2020 or which industry should be preparing for during 2020. SCIP Database ECHA is expected to launch a prototype version of the Substances of Concern In art...




chemical

At least 11 dead, hundreds injured after chemical gas leak at LG Polymers plant in India

A gas leaked from an LG chemical plant in southern India early on Thursday, leaving people struggling to breathe and collapsing in the streets as they tried to flee. At least 11 people died and about 1,000 suffered breathing difficulties and other problems.The synthetic chemical styrene leaked from the LG Polymers plant in a city on India’s eastern coast while workers were preparing to restart the facility after a coronavirus lockdown was eased, state official Vinay Chand said.A fire that broke…




chemical

At Least 5 Dead After Chemical Plant Leak in Southern India

Authorities in southern India say at least five people are dead after a gas leak at an industrial plant Thursday.Over 100 residents in the city of Visakhapatnam were taken to local hospitals after a leak of styrene gas was detected coming from the LG Polymers chemical plant located on the outskirts ...




chemical

Watch the first ever video of a chemical bond breaking and forming

A chemical bond between two metal atoms has been filmed breaking and forming for the first time – something scientists say they only dreamed of seeing




chemical

Don't Miss: absurd animals, the chemical age and DIY dancing

Watch Netflix's Absurd Planet explore weird animals, discover the powerful chemical industry and create dance using a choreographer’s motion-capture moves




chemical

Selenium Helped Cells 'Reboot' After Exposure to Cancer-Causing Chemicals

Title: Selenium Helped Cells 'Reboot' After Exposure to Cancer-Causing Chemicals
Category: Health News
Created: 4/27/2010 2:10:00 PM
Last Editorial Review: 4/28/2010 12:00:00 AM




chemical

Health Tip: Chemical Peel

Title: Health Tip: Chemical Peel
Category: Health News
Created: 5/2/2019 12:00:00 AM
Last Editorial Review: 5/2/2019 12:00:00 AM




chemical

Genetic and Chemical-Genetic Interactions Map Biogenesis and Permeability Determinants of the Outer Membrane of Escherichia coli

ABSTRACT

Gram-negative bacteria are intrinsically resistant to many antibiotics due to their outer membrane barrier. Although the outer membrane has been studied for decades, there is much to uncover about the biology and permeability of this complex structure. Investigating synthetic genetic interactions can reveal a great deal of information about genetic function and pathway interconnectivity. Here, we performed synthetic genetic arrays (SGAs) in Escherichia coli by crossing a subset of gene deletion strains implicated in outer membrane permeability with nonessential gene and small RNA (sRNA) deletion collections. Some 155,400 double-deletion strains were grown on rich microbiological medium with and without subinhibitory concentrations of two antibiotics excluded by the outer membrane, vancomycin and rifampin, to probe both genetic interactions and permeability. The genetic interactions of interest were synthetic sick or lethal (SSL) gene deletions that were detrimental to the cell in combination but had a negligible impact on viability individually. On average, there were ~30, ~36, and ~40 SSL interactions per gene under no-drug, rifampin, and vancomycin conditions, respectively; however, many of these involved frequent interactors. Our data sets have been compiled into an interactive database called the Outer Membrane Interaction (OMI) Explorer, where genetic interactions can be searched, visualized across the genome, compared between conditions, and enriched for gene ontology (GO) terms. A set of SSL interactions revealed connectivity and permeability links between enterobacterial common antigen (ECA) and lipopolysaccharide (LPS) of the outer membrane. This data set provides a novel platform to generate hypotheses about outer membrane biology and permeability.

IMPORTANCE Gram-negative bacteria are a major concern for public health, particularly due to the rise of antibiotic resistance. It is important to understand the biology and permeability of the outer membrane of these bacteria in order to increase the efficacy of antibiotics that have difficulty penetrating this structure. Here, we studied the genetic interactions of a subset of outer membrane-related gene deletions in the model Gram-negative bacterium E. coli. We systematically combined these mutants with 3,985 nonessential gene and small RNA deletion mutations in the genome. We examined the viability of these double-deletion strains and probed their permeability characteristics using two antibiotics that have difficulty crossing the outer membrane barrier. An understanding of the genetic basis for outer membrane integrity can assist in the development of new antibiotics with favorable permeability properties and the discovery of compounds capable of increasing outer membrane permeability to enhance the activity of existing antibiotics.




chemical

Sensory-Directed Genetic and Biochemical Characterization of Volatile Terpene Production in Kiwifruit

Terpene volatiles are found in many important fruit crops, but their relationship to flavor is poorly understood. Here, we demonstrate using sensory descriptive and discriminant analysis that 1,8-cineole contributes a key floral/eucalyptus note to the aroma of ripe 'Hort16A’ kiwifruit (Actinidia chinensis). Two quantitative trait loci (QTLs) for 1,8-cineole production were identified on linkage groups 27 and 29a in a segregating A. chinensis population, with the QTL on LG29a colocating with a complex cluster of putative terpene synthase (TPS)-encoding genes. Transient expression in Nicotiana benthamiana and analysis of recombinant proteins expressed in Escherichia coli showed four genes in the cluster (AcTPS1a–AcTPS1d) encoded functional TPS enzymes, which produced predominantly sabinene, 1,8-cineole, geraniol, and springene, respectively. The terpene profile produced by AcTPS1b closely resembled the terpenes detected in red-fleshed A. chinensis. AcTPS1b expression correlated with 1,8-cineole content in developing/ripening fruit and also showed a positive correlation with 1,8-cineole content in the mapping population, indicating the basis for segregation is an expression QTL. Transient overexpression of AcTPS1b in Actinidia eriantha fruit confirmed this gene produced 1,8-cineole in Actinidia. Structure-function analysis showed AcTPS1a and AcTPS1b are natural variants at key TPS catalytic site residues previously shown to change enzyme specificity in vitro. Together, our results indicate that AcTPS1b is a key gene for production of the signature flavor terpene 1,8-cineole in ripe kiwifruit. Using a sensory-directed strategy for compound identification provides a rational approach for applying marker-aided selection to improving flavor in kiwifruit as well as other fruits.




chemical

Spectral and photochemical diversity of tandem cysteine cyanobacterial phytochromes [Plant Biology]

The atypical trichromatic cyanobacterial phytochrome NpTP1 from Nostoc punctiforme ATCC 29133 is a linear tetrapyrrole (bilin)-binding photoreceptor protein that possesses tandem-cysteine residues responsible for shifting its light-sensing maximum to the violet spectral region. Using bioinformatics and phylogenetic analyses, here we established that tandem-cysteine cyanobacterial phytochromes (TCCPs) compose a well-supported monophyletic phytochrome lineage distinct from prototypical red/far-red cyanobacterial phytochromes. To investigate the light-sensing diversity of this family, we compared the spectroscopic properties of NpTP1 (here renamed NpTCCP) with those of three phylogenetically diverged TCCPs identified in the draft genomes of Tolypothrix sp. PCC7910, Scytonema sp. PCC10023, and Gloeocapsa sp. PCC7513. Recombinant photosensory core modules of ToTCCP, ScTCCP, and GlTCCP exhibited violet-blue–absorbing dark-states consistent with dual thioether-linked phycocyanobilin (PCB) chromophores. Photoexcitation generated singly-linked photoproduct mixtures with variable ratios of yellow-orange and red-absorbing species. The photoproduct ratio was strongly influenced by pH and by mutagenesis of TCCP- and phytochrome-specific signature residues. Our experiments support the conclusion that both photoproduct species possess protonated 15E bilin chromophores, but differ in the ionization state of the noncanonical “second” cysteine sulfhydryl group. We found that the ionization state of this and other residues influences subsequent conformational change and downstream signal transmission. We also show that tandem-cysteine phytochromes present in eukaryotes possess similar amino acid substitutions within their chromophore-binding pocket, which tune their spectral properties in an analogous fashion. Taken together, our findings provide a roadmap for tailoring the wavelength specificity of plant phytochromes to optimize plant performance in diverse natural and artificial light environments.




chemical

Chemical roadblocking of DNA transcription for nascent RNA display [RNA]

Site-specific arrest of RNA polymerases (RNAPs) is fundamental to several technologies that assess RNA structure and function. Current in vitro transcription “roadblocking” approaches inhibit transcription elongation by blocking RNAP with a protein bound to the DNA template. One limitation of protein-mediated transcription roadblocking is that it requires inclusion of a protein factor extrinsic to the minimal in vitro transcription reaction. In this work, we developed a chemical approach for halting transcription by Escherichia coli RNAP. We first established a sequence-independent method for site-specific incorporation of chemical lesions into dsDNA templates by sequential PCR and translesion synthesis. We then show that interrupting the transcribed DNA strand with an internal desthiobiotin-triethylene glycol modification or 1,N6-etheno-2'-deoxyadenosine base efficiently and stably halts Escherichia coli RNAP transcription. By encoding an intrinsic stall site within the template DNA, our chemical transcription roadblocking approach enables display of nascent RNA molecules from RNAP in a minimal in vitro transcription reaction.




chemical

Groundwater chemical characteristics and circulation mode in the Suixiao coal-mining district

Groundwater recharge and runoff conditions are ascertained in the Suixiao coal-mining district using the hydrogen and oxygen isotopes and the trace elements in the unconsolidated pore aquifer of the Cenozoic group, the fissured sandstone aquifer of the Permian system, and the karst fissured limestone aquifer of the Carboniferous Taiyuan Formation and the Ordovician system, which are the main recharge aquifers during coal mining. The main water–rock interactions are pyrite oxidation, cation exchange and adsorption, and carbonate acidification, which are educed by principal component analysis of conventional ions. These results combined with geological conditions prove that hydraulic connection exists generally between the main recharge aquifers, and the groundwater circulation is controlled by faults in the sandstone and limestone aquifers. The water–rock interaction is very weak in the east of the district, which is proved to be a recharge area by Fisher discriminant analysis. This study provides the theoretical basis for the hydrochemistry exploration and the establishment of a water-inrush warning system in a concealed coalfield.




chemical

Multicenter Evaluation of a PCR-Based Digital Microfluidics and Electrochemical Detection System for the Rapid Identification of 15 Fungal Pathogens Directly from Positive Blood Cultures [Mycology]

Routine identification of fungal pathogens from positive blood cultures by culture-based methods can be time-consuming, delaying treatment with appropriate antifungal agents. The GenMark Dx ePlex investigational use only blood culture identification fungal pathogen panel (BCID-FP) rapidly detects 15 fungal targets simultaneously in blood culture samples positive for fungi by Gram staining. We aimed to determine the performance of the BCID-FP in a multicenter clinical study. Blood culture samples collected at 10 United States sites and tested with BCID-FP at 4 sites were compared to the standard-of-care microbiological and biochemical techniques, fluorescence in situ hybridization using peptide nucleic acid probes (PNA-FISH) and matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS). Discrepant results were analyzed by bi-directional PCR/sequencing of residual blood culture samples. A total of 866 clinical samples, 120 retrospectively and 21 prospectively collected, along with 725 contrived samples were evaluated. Sensitivity and specificity of detection of Candida species (C. albicans, C. auris, C. dubliniensis, C. famata, C. glabrata, C. guilliermondii, C. kefyr, C. krusei, C. lusitaniae, C. parapsilosis, and C. tropicalis) ranged from 97.1 to 100% and 99.8 to 100%, respectively. For the other organism targets, sensitivity and specificity were as follows: 100% each for Cryptococcus neoformans and C. gattii, 98.6% and 100% for Fusarium spp., and 96.2% and 99.9% for Rhodotorula spp., respectively. In 4 of the 141 clinical samples, the BCID-FP panel correctly identified an additional Candida species, undetected by standard-of-care methods. The BCID-FP panel offers a faster turnaround time for identification of fungal pathogens in positive blood cultures that may allow for earlier antifungal interventions and includes C. auris, a highly multidrug-resistant fungus.




chemical

18F-rhPSMA-7 PET for the Detection of Biochemical Recurrence of Prostate Cancer After Radical Prostatectomy

18F-labeled prostate-specific membrane antigen (PSMA) PET tracers are increasingly used in preference to 68Ga-PSMA-11 for restaging biochemical recurrence (BCR) of prostate cancer. They are associated with longer half-lives, larger-scale production, and lower positron range than their 68Ga-labeled counterparts. Here, we describe the efficacy of an 18F-labeled radiohybrid PSMA, rhPSMA-7, a novel theranostic PSMA-targeting agent for imaging BCR of prostate cancer. Methods: Datasets from 261 consecutive patients with noncastrate BCR after radical prostatectomy who underwent 18F-rhPSMA-7 PET/CT at our institution between June 2017 and March 2018 were reviewed retrospectively. All lesions suspected of being recurrent prostate cancer were recorded. The detection rate for sites of presumed recurrence was correlated with patients’ prostate-specific antigen (PSA) level, primary Gleason score, and prior therapy (androgen deprivation therapy and external-beam radiation therapy). Results: The 261 patients had a median PSA level of 0.96 ng/mL (range, 0.01–400 ng/mL). The median injected activity of 18F-rhPSMA-7 was 336 MBq, with a median uptake time of 76 min. In total, 211 patients (81%) showed pathologic findings on 18F-rhPSMA-7 PET/CT. The detection rates were 71% (42/59), 86% (44/51), 86% (42/49), and 95% (76/80) at PSA levels of 0.2 to <0.5 ng/mL, 0.5 to <1 ng/mL, 1 to <2 ng/mL, and ≥2 ng/mL, respectively. In 32% patients (7/22) with a PSA of less than 0.2 ng/mL, suggestive lesions were present. 18F-rhPSMA-7 PET/CT revealed local recurrence in 43% of patients (113). Lymph node metastases were present in the pelvis in 42% of patients (110), in the retroperitoneum in 17% (45), and in a supradiaphragmatic location in 8.0% (21). Bone and visceral metastases were detected in 21% (54) and 3.8% (10), respectively. Detection efficacy was not influenced by prior external-beam radiation therapy (79.1% vs. 82.1%, P = 0.55), androgen deprivation therapy within the 6 mo preceding imaging (80.6% vs. 80.9%, P = 0.54), or primary Gleason score (77.9% for ≤7 vs. 82.6% for ≥8, P = 0.38). Conclusion: 18F-rhPSMA-7 PET/CT offers high detection rates in early BCR after radical prostatectomy, especially among patients with low PSA values.




chemical

Molar element ratio analysis of lithogeochemical data: a toolbox for use in mineral exploration and mining

Molar element ratio analysis of element concentrations consists of four basic tools that provide substantial insight into the lithogeochemistry (and mineralogy) of rocks under examination. These tools consist of: (1) conserved element ratio analysis; (2) Pearce element ratio analysis; (3) general element ratio analysis; and (4) lithogeochemical mineral mode analysis. Conserved element ratio analysis is useful in creating a chemostratigraphic model for the host rocks to mineral deposits, whereas Pearce element ratio analysis and general element ratio analysis are primarily used to identify mineralogical and metasomatic controls on rock compositions and to investigate and quantify the extent of the material transfers that formed the host rocks and mineralization. Lithogeochemical mineral mode analysis converts element concentrations into mineral concentrations using a matrix-based change-of-basis operation, allowing lithogeochemical data to be interpreted in terms of mineral modes. It can be used to provide proper names to rocks, an important activity for an exploration geologist because of the implications that rock names have on genetic processes and mineral deposit models.

This paper provides a review of the theoretical foundations of each of these four tools and then illustrates how these techniques have been used in a variety of exploration applications to assist in the search for, evaluation and planning of, and the mining of mineral deposits. Examples include the evaluation of total digestion lithogeochemical datasets from mineral deposits hosted by igneous and sedimentary rocks and formed by hydrothermal and igneous processes. In addition, this paper illustrates a more recent geometallurgical application of these methods, whereby the mineral proportions determined by lithogeochemical mineral mode analysis are used to predict rock properties and obtain the ore body knowledge critical for resource evaluation, mine planning, mining and mine remediation.

Thematic collection: This article is part of the Exploration 17 collection available at: https://www.lyellcollection.org/cc/exploration-17




chemical

State-of-the-art analysis of geochemical data for mineral exploration

Multi-element geochemical surveys of rocks, soils, stream/lake/floodplain sediments and regolith are typically carried out at continental, regional and local scales. The chemistry of these materials is defined by their primary mineral assemblages and their subsequent modification by comminution and weathering. Modern geochemical datasets represent a multi-dimensional geochemical space that can be studied using multivariate statistical methods from which patterns reflecting geochemical/geological processes are described (process discovery). These patterns form the basis from which probabilistic predictive maps are created (process validation). Processing geochemical survey data requires a systematic approach to effectively interpret the multi-dimensional data in a meaningful way. Problems that are typically associated with geochemical data include closure, missing values, censoring, merging, levelling different datasets and adequate spatial sample design. Recent developments in advanced multivariate analytics, geospatial analysis and mapping provide an effective framework to analyse and interpret geochemical datasets. Geochemical and geological processes can often be recognized through the use of data discovery procedures such as the application of principal component analysis. Classification and predictive procedures can be used to confirm lithological variability, alteration and mineralization. Geochemical survey data of lake/till sediments from Canada and of floodplain sediments from Australia show that predictive maps of bedrock and regolith processes can be generated. Upscaling a multivariate statistics-based prospectivity analysis for arc-related Cu–Au mineralization from a regional survey in the southern Thomson Orogen in Australia to the continental scale, reveals a number of regions with a similar (or stronger) multivariate response and hence potentially similar (or higher) mineral potential throughout Australia.

Thematic collection: This article is part of the Exploration 17 collection available at: https://www.lyellcollection.org/cc/exploration-17




chemical

New developments in field-portable geochemical techniques and on-site technologies and their place in mineral exploration

This paper focuses on handheld and top-of-hole techniques which have appeared since 2007 or have undergone major improvements, and discusses their benefits, challenges and pitfalls, why we use them and what to expect from them. There is an ongoing need to be innovative with the way we undertake mineral exploration. Recent technological advances that have been applied to successful mineral exploration include on-site or portable instruments, on-site laboratory technologies, various core scanners, and technologies for fluid analysis. Portable or field technologies such as pXRF, pXRD, pNIR-SWIR, µRaman and LIBS aid in obtaining chemical and mineralogical information. Spectral gamma tools, a well-known technology, recently took advantage of improved ground and airborne (drone) instruments, to complement hyperspectral imagery. At mine and exploration sites, top-of-hole sensing technologies, such as Lab-at-Rig® and various core scanners (both spectral- and XRF-based) have become useful tools to analyse metres of core as it is being drilled. Fluid analyses are not as common as analyses of solid materials, but there are advances in such technologies as anodic stripping voltammetry, polarography and ion-exchange electrodes aiming for analysis of commodity or environmentally important elements.

Field-portable geochemical techniques and on-site technologies now offer instant response and flexibility for most exploration tasks. By providing relevant data within minutes, they allow safer field decisions and focus on the most promising finds, while saving valuable resources in sampling grids or drilling. More efficient laboratory analysis programs are supported by sample screening and homogeneity checking on-site. Field analyses are not always as accurate as laboratory ones, but most of the time can be correlated with them, enabling reliable decisions. The level of confidence in field-made decisions needs to be compared between later and less numerous laboratory analyses, and less precise but more abundant and immediate field analyses. It may be demonstrated that, in many cases, the fit–for-purpose nature of the latter allows a better confidence level. Quality compromises associated with field analyses can be reduced by the application of better sample preparation and quality assurance/quality control (QA/QC) procedures. Most of the further development of on-site chemical analysis is expected to be based on its integration with lab methods and on sound QA/QC practice, allowing a precise evaluation of its confidence level and uncertainties. Mineralogical analyses are constrained by our ability to interpret the data in near-real time but offer promising approaches in both surface and drilling exploration campaigns.

Thematic collection: This article is part of the Exploration 17 collection available at: https://www.lyellcollection.org/cc/exploration-17




chemical

Advances in the use of isotopes in geochemical exploration: instrumentation and applications in understanding geochemical processes

Among the emerging techniques to detect the real footprint of buried ore deposits is isotope tracing. Novel and automated preparation systems such as continuous flow isotope ratio mass spectrometry, off-axis integrated cavity output spectroscopy for isotopic compositions of selected molecules, multi-collector inductively coupled-plasma mass spectrometry (ICP-MS), triple quadrupole ICP-MS, laser ablation ICP-MS, and a multitude of inline preparation systems have facilitated the use of isotopes as tracers in mineral exploration, as costs for isotope analyses have decreased and the time required for the analyses has improved. In addition, the isotope systems being used have expanded beyond the traditional light stable and Pb isotopes to include a multitude of elements that behave differently during processes that promote the mobilization of elements during both primary and secondary dispersion. Isotopes are also being used to understand barren areas that lack a critical process to form an ore deposit and to reveal precise redox mechanisms. The goal is to be able to use isotopes to reflect a definitive process that occurs in association with the deposit and not in barren systems, and then to relate these to something that is easier to measure, namely elemental concentrations. As new generations of exploration and environmental scientists are becoming more comfortable with the application of isotopes to effectively trace processes involved in geoscience, and new technologies for rapid and inexpensive analyses of isotopes are continually being developed, novel applications of isotope tracing are becoming more mainstream.

Thematic collection: This article is part of the Exploration 17 collection available at: https://www.lyellcollection.org/cc/exploration-17




chemical

Recent advances in the application of mineral chemistry to exploration for porphyry copper-gold-molybdenum deposits: detecting the geochemical fingerprints and footprints of hypogene mineralization and alteration

In the past decade, significant research efforts have been devoted to mineral chemistry studies to assist porphyry exploration. These activities can be divided into two major fields of research: (1) porphyry indicator minerals (PIMs), which are used to identify the presence of, or potential for, porphyry-style mineralization based on the chemistry of magmatic minerals such as zircon, plagioclase and apatite, or resistate hydrothermal minerals such as magnetite; and (2) porphyry vectoring and fertility tools (PVFTs), which use the chemical compositions of hydrothermal minerals such as epidote, chlorite and alunite to predict the likely direction and distance to mineralized centres, and the potential metal endowment of a mineral district. This new generation of exploration tools has been enabled by advances in and increased access to laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), short-wave length infrared (SWIR), visible near-infrared (VNIR) and hyperspectral technologies. PIMs and PVFTs show considerable promise for exploration and are starting to be applied to the diversity of environments that host porphyry and epithermal deposits globally. Industry has consistently supported development of these tools, and in the case of PVFTs encouraged by several successful blind tests where deposit centres have successfully been predicted from distal propylitic settings. Industry adoption is steadily increasing but is restrained by a lack of the necessary analytical equipment and expertise in commercial laboratories, and also by the ongoing reliance on well-established geochemical exploration techniques (e.g. sediment, soil and rock chip sampling) that have aided the discovery of near-surface resources over many decades, but are now proving less effective in the search for deeply buried mineral resources and for those concealed under cover.

Thematic collection: This article is part of the Exploration 17 collection available at: https://www.lyellcollection.org/cc/exploration-17




chemical

Investigating the Effects of the Chemical Composition on Glass Corrosion: A Case Study for Type I Vials

Glass is the favorite material for parenteral packaging because of its physico-chemical properties. Type I borosilicate glass is worldwide use at this scope, but it may have some issues related to breakage, corrosion and delamination that might compromise the drug quality, safety and efficacy. These issues can be mitigated and avoided starting from the appropriate selection of the most suitable raw material at the early stage of the glass container design. In this study, Type I borosilicate glass vials manufactured using two glass tubes having different chemical compositions, were studied and compared in terms of their resistance to corrosion. Testing design was applied with the aim to select the best practice approach comparing different storage simulation conditions: ageing treatment through autoclaving and stability testing (real-time and accelerated). Clear differences were found between the different glass types in terms of hydrolytic and corrosion resistance that highlighted the relation between chemical composition and glass chemical durability. Non-negligible differences were also observed using different storage conditions.




chemical

Vizag Gas Leak: Locals Protest, Want Relocation of Chemical Plant

Locals staged a protest at the chemical plant in R R Venkatapuram in Vizag demanding relocation of the factory.





chemical

At least eight dead and thousands taken to hospital after chemical leak in India

The incident led to panic among locals within a three-kilometre radius.




chemical

Gas leak at Indian chemical plant kills 11

Visakhapatnam, India (AFP) May 7, 2020
Eleven people were killed and hundreds hospitalised after a pre-dawn gas leak at a chemical plant in eastern India on Thursday that left unconscious victims lying in the streets, authorities said. Fears that the death toll from the incident on the outskirts of the Visakhapatnam, an industrial port city in Andhra Pradesh state, were not borne out however. The gas escaped out of tanks at a




chemical

How a chemicals company is helping with the Covid-19 pandemic

Chemicals company Lubrizol is helping with the pandemic by making materials used in Personal Protection Equipment (PPE) as well as hand sanitiser and products to help treat patients who are fighting the virus.




chemical

Mitsubishi Chemical America acquires Gelest

Mitsubishi Chemical America has entered into a definitive agreement to acquire all of the issued and outstanding shares of Gelest Intermediate Holdings, the parent of Gelest, and a portfolio company of New Mountain Capital.




chemical

USPTO Biotechnology/Chemical/Pharmaceutical Customer Partnership Meeting

Biotechnology/Chemical/Pharmaceutical Customer Partnership   Wednesday, June 8, 2011 Meeting  Madison Auditorium   Starting Time of 10:00 AM  United States Patent and Trademark Office Alexandria, Virginia  600 Dulany Street, Alexandria, VA,  Accessing the event: Double click on the link below (or copy it into your internet browser) https://uspto.connectsolutions.com/r80345544/ Click here   for detailed login instructions in MS Word.   […]




chemical

Two Chemical Companies Agree to Resolve Environmental Violations in Ohio

The former and current owners and operators of a chemical facility in Addyston, Ohio, LANXESS Corp. and INEOS ABS USA Corp., have agreed to pay a $3.1 million civil penalty and INEOS will spend up to $2 million to install environmental controls and modify operating procedures to resolve violations of multiple environmental laws.



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