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Nanorod structures exhibit a high surface-to-volume ratio, enhancing the accessibility of electrolyte ions to the electrode surface and providing an abundance of active sites for improved electrochemical sensing performance. In this study, tetragonal α-MnO2 with a large K+-embedded tunnel structure, directly grown on microfibrous carbon paper to form densely packed nanorod arrays, is investigated as an electrocatalytic material for non-enzymatic glucose sensing. The MnO2 nanorods electrode demonstrates outstanding catalytic activity for glucose oxidation, showcasing a high sensitivity of 143.82 µA cm−2 mM−1 within the linear range from 0.01 to 15 mM, with a limit of detection (LOD) of 0.282 mM specifically for glucose molecules. Importantly, the MnO2 nanorods electrode exhibits excellent selectivity towards glucose over ascorbic acid and uric acid, which is crucial for accurate glucose detection in complex samples. For comparison, a gold electrode shows a lower sensitivity of 52.48 µA cm−2 mM−1 within a linear range from 1 to 10 mM. These findings underscore the superior performance of the MnO2 nanorods electrode in both sensitivity and selectivity, offering significant potential for advancing electrochemical sensors and bioanalytical techniques for glucose monitoring in physiological and clinical settings. [ABSTRACT FROM AUTHOR]

BACKGROUND: Flexible surface‐enhanced Raman spectroscopy (SERS) substrates such as paper‐based substrates show great potential for rapid detection of residual chemicals on food surfaces. However, controlling the density and distribution of metallic nanoparticles adsorbed on the paper is still challenging. RESULTS: The amount of gold (Au) nanospheres (51 ± 4 nm) attached on the filter paper modified with 3‐aminopropyltriethoxysilane (APTES) was tunable, increasing as the level of APTES (2.5–15.0 g kg−1) applied for paper modification increased. Moreover, the Au nanospheres were relative evenly distributed on the filter paper modified with 2.5–10.0 g kg−1of APTES, which resulted in excellent intra‐ and inter‐reproducibility of SERS signals for pesticides including thiram, diquat dibromide, and paraquat dichloride (relative standard deviation = 2.2–10.1%). The modified paper‐based substrate could be used to detect as low as 0.05–0.2 mg L−1 of pesticides in standard solutions, and as low as 5–20 ng cm−2 of residual pesticides on apple skins with minimum sample pretreatment. CONCLUSION: This paper‐based substrate with tunable feature for the density and distribution of nanoparticles is applicable for rapid SERS detection of residual pesticides in fruits and vegetables. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Paper‐based analytical devices as a low‐cost and point‐of‐care sensing platform have attracted widespread research interest. However, the device fabrication and signal readout remain a challenge for their real‐world applications. Herein, a technically simple paper‐based sensor is developed by taking advantage of the easily accessible paper and the plasmonic property of gold nanomaterials. The sensing mechanism relies on the iodide‐mediated surface etching of gold nanostars that induces a color change from blue to red of the paper strip. The versatility of the paper substrate in size, shape, and materials allows for the facile immobilization of gold nanostars by a simple immersing method, which is easy to operate and free from specialized skills and equipment. In addition, the readout of the paper strip can be conveniently visualized by the naked eye or through a smartphone. This paper‐based sensor advantages in low cost, light weight, easy handling, and disposability that holds great promise as a point‐of‐care detection platform in resource‐constrained settings. [ABSTRACT FROM AUTHOR]

The significant development in the electronic commerce market has led to new issues in commerce in general and e-commerce in particular, especially in the trade of purchasing gold with paper currency. Therefore, it has become necessary to explore the Islamic rulings related to this type of trade. The research aims to: • Clarify the Islamic ruling on purchasing gold with paper currency through the internet. • Examine the principles that determine the ruling on purchasing gold with paper currency through the internet. • Describe the various methods of purchasing gold with paper currency through the internet. Research Methodology: Inductive and analytical methods. Among the most prominent findings of the researcher are: • Money is anything that is generally accepted in trading, used as a medium of exchange, a measure of value, and a store of wealth. • There are three types of money: commodity money, metallic money, and paper money. The first to use paper money were the Chinese. • It is permissible to purchase gold with paper currency with the authorization of receipt at the time of the contract. [ABSTRACT FROM AUTHOR]

• A stack-up micro electrochemical device was developed based on the carbon paper electrode. • Cobalt-based MOFs and gold nanoparticles improved the metal ion absorption and electron diffusion. • Sensitive simultaneous determination of Pb2+ and Cd2+ achieved the subnanogram LODs. A portable device is conducive to the on-site detection of heavy metal ions at trace level in food and the prevention of related food safety issues. In this work, an electrochemical device stacked up with flat electrodes was developed for the detection of Pb2+ and Cd2+. The top layer of the device is a carbon paper as working electrode, which is modified with amino functionalized cobalt-based metal-organic framework and gold nanoparticles. The bottom layer was constructed with the carbon counter electrode and Ag/AgCl reference electrode, and a punched sample cell (Φ = 8 mm) was in the middle. The proposed method could simultaneously determinate Pb2+ and Cd2+ via anodic stripping voltammetry with the detection limit of 7.0 × 10−2 ng mL−1 and 1.1 × 10−2 ng mL−1, and was applied in real food samples (drinking water, juice, tea, grain, fruits, vegetables, liver and aquatic products) with the recovery of 91.2–105.4 % and 90.2–111.2 %, respectively. [ABSTRACT FROM AUTHOR]

In this article, we report the convenient preparation of graphene/gold nanoparticle-decorating filter membrane, which could be directly used as electrode for H2O2 sensing. The graphene oxide and chloroauric acid are reduced by L-ascorbic acid before covering the paper substrate. The reduced graphene oxide/gold nanoparticle-paper material is characterized by scanning electron microscopy, X-ray diffraction and Raman spectroscopy. The paper composite could be cut into piece and directly used as electrochemical sensor. The electrochemical experimental results show that the paper sensor has satisfying performances in sensing H2O2 with the detection limit of 15 μM and the linear range is 8.53-17.35 mM. This work would propose a novel strategy for the applications of graphene in the fields of electroanalysis and sensing. [ABSTRACT FROM AUTHOR]

Signal amplification in colorimetric biosensors usually requires labile reagents and/or additional steps, which are not ideal for in-field measurements. Here we show that the limit of detection of a gold nanoparticle-labeled colorimetric immunosensor can be decreased 10-fold by performing the assay on a folded piece of paper. In this approach, the intrinsic porosity of the substrate enables generating multiple signals with a single drop of reagent. This yields combined signals with higher optical density thanks to the semitransparent nature of the wet material. It will be shown that this method can decrease the limit of detection 10 times in a model immunosensor for the detection of immunoglobulins. The procedure is so straightforward that it could be easily implemented to decrease the limit of detection of microfluidic paper-based analytical devices with colorimetric readouts. [ABSTRACT FROM AUTHOR]

Advanced gold (Au) and silver (Ag) nanostructures were produced by laser techniques on printer paper substrate. Surface-enhanced Raman spectroscopy (SERS) analyses of the fungicide mancozeb (Dithane DG) and insecticide thiamethoxam (Aktara 25 BG) in quantities smaller than usually applied in agricultural medicine were performed for the first time assisted by the structures fabricated. The investigations and results show an easy alternative and cheap way to detect small amounts or residue of harmful environmental pollutants, which has a direct bearing on food quality and thus on human health. [ABSTRACT FROM AUTHOR]

This paper challenges current approaches to undertaking community‐centred disaster recovery. Community‐centred approaches are widely recognised as ‘the gold standard’ for effective recovery from disasters. Yet, they are rarely applied well enough in practice. Challenges include the ‘authority’ culture of command‐and‐control agencies, the emphasis on discrete recovery time frames, and the reluctance to relinquish centralised control. The paper focuses on people's experiences of community‐centred recovery in New South Wales, Australia, which has experienced severe fires and floods since 2019. We undertook key informant interviews and an online survey to inquire into how community‐centred recovery is enacted. Our work uncovered widespread dissatisfaction with current practices. The paper discusses key themes emerging from the research and ends with a call to change how community‐centred recovery is framed and conducted by responding organisations, to include the underlying causes of vulnerability in recovery, to measure success differently, and to alter the narrative of who ‘owns’ disasters. [ABSTRACT FROM AUTHOR]

Abstract: Cellulose paper has been discovered as a smart material including actuating behavior and electro-active paper (EAPap) with application of electric field. To control the electro-active motion, the EAPap requires electronic components on the paper. However, conventional lithography technique cannot apply to the paper to fabricate electronic components due to its hydrophilic nature, water absorption, and flexibility. For this reason, a micro-contact printing (MCP) technique was employed to fabricate Au patterns on the EAPap. Large number of Au-islands and irregular edge patterns were observed on the transferred Au-pattern when the self-assembled monolayer (SAM) was fabricated on the cellulose surface. Therefore, SAM was fabricated on the Au-surface. The surface quality of the transferred Au was strongly dependent on the solvent polarity. Better surface morphology of the transferred Au-pattern was obtained with the polar solvent compared with nonpolar solvent. [Copyright &y& Elsevier]

Detecting variations in the localized surface plasmon resonance (LSPR) of gold nanoparticles is a widespread approach for developing colorimetric biosensors. This is usually performed with a large spectrophotometer, which is not suitable for in-field measurements, or with the naked eye, which only allows detecting large spectral variations leading to clear changes in color. Here we demonstrate that patterns printed on paper can transduce LSPR variations caused by the aggregation of plasmonic nanosensors using a mobile device as the reader. The sensitivity of the proposed paper transducers is tested with a new enzyme-less signal generation mechanism for biosensors based on triggering the aggregation of gold nanoparticles in the presence of neutravidin. A competitive immunoassay using this mechanism and the proposed transducers can detect the model analyte C-reactive protein with a limit of detection of 3·10 −8  g mL −1 within 1 h, which is comparable to an ELISA using a spectrophotometer to detect the signal. The fabrication of the transducers only requires a common toner printer, and the signal can be detected with the ubiquitous smartphone using a downloadable app, which makes the proposed detection platform ideal for developing mobile biosensors for global health applications. [ABSTRACT FROM AUTHOR]

Herein we report a time and cost – effective approach for rapid determination of Cadmium (Cd) in rice based on electrochemical detection in paper-based analytical devices (PADs). Specifically, double sided conductive carbon tape coated with a thin layer of gold was used as the disposable electrochemical sensors for stripping analysis of Cd (II) coupled with in situ electrodeposition of bismuth. With the gold sputtering time of just 10 s the maximum electrochemical responses of Cd (II) could be obtained, suggesting that retained nanostructure of the carbon tape might facilitate the stripping analysis based on differential pulsed voltammetry. Under optimized experimental parameters, the concentration of Cd (II) from 2 to 150 μg L −1 could be linearly detected with the detection limit of 0.1 μg L −1 . Because of the requirement of low sample volumes in PADs, more importantly, our approach could quantify Cd in rice samples with the weight of about two hundreds of milligrams, which could be treated using a muffle burner with the duration of around one hour. This study implied the practical potential of paper-based analytical devices in the field of rapid detection. [ABSTRACT FROM AUTHOR]

A binder-free and flexible Au electrode is prepared by spontaneous deposition of Au onto a A4 (A4-paper)-8B (8B pencil)-Ni Film substrate (ABNi) which is assembled by electrodeposition of nanoscale Ni particles on the surface of A4 paper coated by 8B pencil. The morphology and phase structure of the (A4-paper)-8B (8B pencil)-Ni Film-Au (ABNiAu) electrode are characterized by scanning electron microscopy equipped with energy dispersive X-ray spectrometer and X-ray diffractometer. The catalytic activity of the ABNiAu electrode for NaBH 4 electrooxidation is investigated by means of cyclic voltammetry and chronoamperometry. The electrode exhibits a high electric conductivity and the activity substance attaches to the surface of paper substrate tightly and does not fall off at all and the nanoscale Ni and Ni Au alloy enhance the broken of the B H bond in the BH 4 − , all of which lead to a high catalytic activity for NaBH 4 electrooxidation. The oxidation current density reaches 300 mA cm −2 in 1 mol dm −3 NaOH and 0.1 mol dm −3 NaBH 4 at −0.2 V. The exchanged electrons (n) is 6.0 (8.0 in theory), which indicates that the ABNiAu electrode has much higher utilization efficiency of the fuel than our reported LaNi 5 /Pd (n = 4) electrode. [ABSTRACT FROM AUTHOR]

This study proposes a methodology using OpenAlex (OA) for tracking Open Access publications in the case of Argentina, a country where a self-archiving mandate has been in effect since 2013 (Law 26.899, 2013). A sample of 167,240 papers by researchers from the Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) was created and analyzed using statistical techniques. We estimate that OA is able to capture between 85-93% of authors for all disciplines, with the exception of Social Sciences and Humanities, where it only reaches an estimated 47%. The availability of papers in Open Access was calculated to be 41% for the period 1953-2021 and 46% when considering exclusively the post-law period (2014-2021). In both periods, gold Open Access made up the most common route. When comparing equal periods post and pre-law, we observed that the upward trend of gold Open Access was pre-existing to the legislation and the availability of closed articles in repositories increased by 5% to what is estimated based on existing trends. However, while the green route has had a positive evolution, it has been the publication in gold journals that has boosted access to Argentine production more rapidly. We concluded that the OA-based methodology, piloted here for the first time, is viable for tracking Open Access in Argentina since it yields percentages similar to other national and international studies. [ABSTRACT FROM AUTHOR]

Abstract: Gold is among the highly conductive and stable materials, which are ideal anodes for microbial fuel cells (MFCs). However, previous studies have shown that bare gold surface is recalcitrant for the colonization of some exoelectrogens, e.g., Shewanella putrefacians. In this work, the problem regarding the poor bio-compatibility of gold as an anode material was sorted out through coupling it with carbon paper. A new composite anode material was fabricated through sputtering gold layer homogeneously on carbon paper matrix. Results of cyclic voltammetry and electrochemical impedance spectroscopy in Fe(CN)6 3−/4− solution demonstrated better electrochemical performance of the carbon paper–gold (C–Au) composite than either carbon paper or bare gold, when they were used in MFCs. With Shewanella oneidensis MR-1 as the inoculum, the C–Au anode-based MFC produced total electric charges higher than the carbon-paper-anode-based MFC by 47%. The cyclic voltammetry analysis and the scanning electron microscopy observation showed that the MR-1 biofilm growth was accelerated when the carbon paper surface was sputtered with gold. Utilization of such a carbon paper–gold composite significantly enhanced the MFC performance. [ABSTRACT FROM AUTHOR]

This paper describes the development of simple, sustainable, and low-cost strategies for signal enhancement on paper-based carbon platforms through gold nanoparticles electrogenerated from small volumes of tetrachloroauric (III) acid solutions. Carbon ink is deposited on a hydrophilic working area of the paper delimited with hydrophobic wax. This maskless procedure is fast and cuts down ink waste. The connection of this working electrode to the potentiostat is ensured with the use of screen-printed electrodes (SPEs). Close contact of the whole area of both carbon electrodes improves the precision of the nanostructuration. Resulting gold-modified paper-based carbon working electrodes (AuNPs-PCWEs) were characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), and electron dispersion X-ray spectrometry (SEM/EDX). This methodology was applied for the first time to the inorganic arsenic determination in commercial white wines by chronoamperometric stripping of the electrodeposited As(0). In an optimized system, As(III) was reduced and deposited as As(0) on the nanostructured surface by applying a potential of -0.3 V during 180 s. Then, anodic stripping chronoamperometry was performed at +0.4 V. The analytical signal was the current recorded at 30 s. On the other hand, As(V) was chemically reduced to As(III) with 0.2 M KI, and total determination of arsenic could be carried out. As(V) was determined as the difference between total As and As(III). Then, this fast, simple and low-cost method can be employed for speciation purposes. Limits of detection for As(III) and total arsenic (in the presence of KI) are 2.2 µg L-1 and 2.4 µg L-1, respectively, and indicate that this method is suitable for regulated quality control. [ABSTRACT FROM AUTHOR]

Cellulose paper was prepared and utilized as a substrate for flexible top emission organic light-emitting diodes (TE-OLEDs). We successfully fabricated flexible TE-OLEDs with Ni and Au anodes on SiO2/cellulose paper substrate. The SiO2barrier layer coated on the cellulose paper substrate enhanced the surface roughness of the cellulose paper substrate. The surfaces of 100 nm thick Ni and Au films on SiO2/cellulose paper substrate become continuous on the SiO2/cellulose paper substrate, resulting in low sheet resistance of the Ni and Au films. While the maximum luminance of the flexible TE-OLED with Au anode was about 3516 cd/m2at a driving voltage of 12 V, that of the flexible TE-OLEDs with Ni anode was 1280 cd/m2at a driving voltage of 10 V. [ABSTRACT FROM PUBLISHER]

The given text appears to be a scientific article or research paper that provides detailed information on the crystal structures of various mixed-valence gold compounds. The compounds contain gold(I) and gold(III) atoms, as well as different ligands such as sulfur, phosphorus, and selenium. The text discusses the structures, compositions, and supramolecular features of the compounds, including bond lengths, angles, and interionic contacts. It also provides information on the synthesis and characterization of the compounds, as well as their crystallographic data and refinement details. Overall, the text is a valuable resource for researchers studying the properties and structures of gold compounds. [Extracted from the article]

The paper presents a study of typomorphic characteristics of placer gold from tributaries of the Kengeveem River, Magadan oblast. The placer gold was studied by optical and scanning electron microscopy at the Institute of Volcanology and Seismology, Far Eastern Branch, Russian Academy of Sciences. As a result, the first information on the morphology, internal structure, and chemical composition of placer gold from the southeastern Taigonos Peninsula was obtained. Three mineral types of the gold were determined. The first type is dominant. Its grains are characterized by subore morphology, with weak and medium roundness. Only Au and Ag are present in the composition of native gold, other macrocomponents were not found. The gold fineness is 750‒950‰. Some gold grains bear signs of supergene transformation, which is expressed in the development of high-fineness gold rims and intergranular veins. The second type of the gold is represented by well-rounded plates with a fineness of 980‒990‰. The third type is loose aggregates of secondary high-grade mustard gold. The obtained data allowed us to determine the different transport distances of native gold and to consider the low-sulfide epithermal Au‒Ag mineralization and presumably distal gabbroids as the primary sources of gold. [ABSTRACT FROM AUTHOR]

Introduction: This paper explores the fate of South Australia's highly regarded Police Drug Diversion Initiative over the past 10 years. Methods: The paper uses historical and legal analysis, including publicly available data as to rates of drug use, arrests and diversions, media reports, legislation and Hansard debates. Results: In the mid‐2010s, amidst growing anxiety about levels of amphetamine‐type stimulants use in Adelaide, a coroner's report became the poster child for what was seen by the Liberal opposition as the excessive leniency and 'waste of resources' of the Police Drug Diversion Initiative. Despite being universally praised for its efficacy, the Liberal government, when elected, passed amendments to the legislation which 'capped' diversions at two. This ended the period in which diversions from criminal to social justice systems was mandatory for all persons charged with simple drug possession. But since then, the diversion rate in South Australia has plummeted in ways that cannot be explained merely because of these amendments. Discussion and Conclusions: The most highly regarded scheme for diversion of minor drug offenders to treatment is no longer effective. Indeed, the best scheme in the country may now be the worst. The essay draws attention to a catastrophe whose extent is not yet fully appreciated and suggests ways in which we can begin to explain why such a small change has had such dramatic and unforeseen consequences. Like some sort of perverse alchemy, Australia's gold standard for drug diversion has been turned into lead. [ABSTRACT FROM AUTHOR]

Abstract: The construction of electromechanical actuator has been achieved by using the conducting polypyrrole films deposition onto a gold-coated cellophane paper. This is probably the first report of this type of paper actuator. The conducting polypyrrole was electro-generated using either galvanostatic or potentiostatic conditions at 0.5mA/cm2 current density or 0.7V applied potential, respectively. The two types of actuators were constructed, namely: (1) Ppy/cellophane bi-layer; (2) Ppy/cellophane paper/Ppy tri-layer. These actuators showed a reversible and reproducible displacement in acetonitrile solution containing LiClO4 (1M). The maximum displacement of 9.1mm was recorded for tri-layer device and 3.5mm for bi-layer device in 1M LiClO4 acetonitrile solutions. The results obtained in acetonitrile solution containing 1M LiClO4 shows that the actuator requires very low excitation voltage of 0.2MVm−1. The mechanism for this paper actuation phenomenon is addressed in this paper. [Copyright &y& Elsevier]

Abstract: We report the application of free-standing, lightweight, and flexible graphene/Au composite paper (GACP), as a current collector for CF x cathode. At a high discharge current density of 4000 mA g−1 (5C), the capacity of the CF1.0 loaded on GACP current collector is 653 mAh g−1, while CF1.0 loaded on Al foil failed at 800 mA g−1 (1C). Using GACP, both excellent rate capability and specific capacity can be achieved simultaneously, owing to its undulant surface structure and flexible contact with the CF x composite active layer. Our results provide a new strategy to design both high power and energy densities CF x cathode. [Copyright &y& Elsevier]

Abstract: Through a simple and rapid method, carbon papers (CPs) were coated with Au and the resulting Au/CP substrates were used for the preparation of Pt/Au/CP by Cu underpotential deposition (Cu UPD) and redox replacement technique. A series of Pt n /Au/CP catalysts (where n = number of UPD-redox replacement cycles) were synthesized and their electrochemical properties for methanol oxidation reaction (MOR), and oxygen reduction reaction (ORR) were investigated by electrochemical measurements. The Pt n /Au/CP electrodes show higher electrocatalytic activity and enhanced poison tolerance for the MOR as compared to a commercial Pt/C on CP (Pt/C/CP). The highest mass specific activity and Pt utilization efficiency for MOR was observed on Pt1/Au/CP with a thickness close to a monatomic Pt layer. Chronoamperometric tests in methanol solution revealed that Pt n /Au/CPs have much higher CO tolerance compared to Pt/C/CP. Among the Pt n /Au/CPs, CO tolerance decreases with increasing the amount of deposited Pt, indicating that the exposed Au atoms in close proximity to Pt plays a positive role against CO poisoning. Compared with the Pt/C/CP, all the Pt n /Au/CP electrodes show more positive onset potentials and lower overpotentials for ORR. For instance, the onset potential of ORR is 150 mV more positive and the overpotential is ∼140 mV lower on Pt4/Au/CP with respect to Pt/C/CP. [ABSTRACT FROM AUTHOR]

The majority of bioassays utilize thermosensitive reagents (e.g., biomolecules) and laboratory conditions for analysis. The developing world, however, requires inexpensive, simple-to-perform tests that do not require refrigeration or access to highly trained technicians. To address this need, paper-based bioassays using gold nanoparticle (AuNP) colorimetric probes have been developed. In the two prototype DNase I and adenosine-sensing assays, blue (or black)-colored DNA-cross-linked AuNP aggregates were spotted on paper substrates. The addition of target DNase I (or adenosine) solution dissociated the gold aggregates into dispersed AuNPs, which generated an intense red color on paper within one minute. Both hydrophobic and (poly(vinyl alcohol)-coated) hydrophilic paper substrates were suitable for this biosensing platform; by contrast, uncoated hydrophilic paper caused "bleeding" and premature cessation of the assay due to surface drying. The assays are surprisingly thermally stable. During preparation, AuNP aggregate-coated papers can be dried at elevated temperatures (e.g., 90 °C) without significant loss of biosensing performance, which suggests the paper substrate protects AuNP aggregate probes from external nonspecific stimuli (e.g., heat). Moreover, the dried AuNP aggregate-coated papers can be stored for at least several weeks without loss of the biosensing function. The combination of paper substrates and AuNP colorimetric probes makes the final products inexpensive, low-volume, portable, disposable, and easy-to-use. We believe this simple, practical bioassay platform will be of interest for use in areas such as disease diagnostics, pathogen detection, and quality monitoring of food and water. [ABSTRACT FROM AUTHOR]

Metal modified paper-based substrates were utilized for microfluidic paper-based solution sampling coupled with Pb2+-ion selective electrodes (ISEs) with the aim of controlling the super-Nernstian response which usually occurs when using unmodified paper substrates. Potentiometric responses of Pb2+-ISEs coupled with gold, platinum and palladium coated paper substrates were investigated. Potentiometric response time was found to be predominantly dependent on the thickness of metallic layer deposited at the paper substrates. Paper-based substrates coated on both sides with 38 nm gold layers were found to be the most advantageous in controlling the super-Nernstian response of ISEs at non-equilibrium conditions. Durability studies indicated that the lifetime of Pb2+-ISEs could be doubled when used with paper-based substrates in complex environmental samples with high solid-to-liquid content. Determination of lead in real samples using metal modified paper substrates coupled with Pb2+-ISEs was validated by inductively coupled plasma optical emission spectrometry (ICP-OES). Detailed life cycle assessments were performed for model screen printed potentiometric sensors with and without metal modified paper-based solution sampling substrates. The results confirmed that the use of modified paper substrates demonstrated lower environmental impact per potentiometric measurement of Pb2+-ISE in prepared simulated environmental sample as compared to sensors without the use of paper substrates. [Display omitted] • Metal modified paper substrates allowed to control response of lead(II) ISEs. • Non-equilibrium based potentiometric system was developed. • Determination of lead in complex environmental samples was successfully performed. • Life cycle assessment was used to evaluate environmental impacts of potentiometry. [ABSTRACT FROM AUTHOR]

In this paper, the effects of an ultrasonic power and the intensity of mechanical agitation for pulp on alkaline pretreatment of gold-bearing arsenopyrite were investigated. The effect of pulp temperature on leaching efficiency in alkaline pretreatment of arsenopyrite was investigated under ultrasound and non-ultrasound conditions. Pre-treatment was followed by gold leaching tests with a cyanide solution. Compared with the nonultrasound condition at the temperature of 60 ○C, arsenic extraction and gold extraction was increased 20 %, 14.4 %, respectively, in the presence of ultrasound at ambient temperature. The characteristics of the ultrasonic power level as a function of the intensity of mechanical agitation were evaluated by a numerical simulation with CFD software – Ansys Fluent. The simulation results demonstrated that the stronger intensity of mechanical agitation, the lower ultrasonic power level. These results were proved through leaching experiments at different rotation speeds of impeller and ultrasonic powers. The study results demonstrate that the ultrasound is an effective factor for pretreatment of gold bearing arsenopyrite and gold extraction is related to an ultrasonic power and the intensity of mechanical agitation. [ABSTRACT FROM AUTHOR]

This paper reports white solid-state lighting potential of gold nanoparticles-embedded Dy3+-doped Li2CO3–SrO–ZnO–B2O3 glasses prepared using melt quenching. The produced materials undergo characterizations using various instrumentations to assess the sensitivity of changing AuNP concentrations on their emission characteristics. XRD phase analysis established that the samples were glasses. TEM analysis shows AuNPs, whereas EDX spectroscopic analysis confirmed the inclusion of precursor elements into the glasses. The thermal stability, Hruby parameter, and glass-forming ability are 146–156 °C, 1.27–1.39 and 66–0.65 respectively. The optical absorption spectra of the glasses are consistent with Dy3+ transitions, while the surface plasmon resonance band fits the AuNPs characteristics band. The emission spectroscopic analysis reveals intensification factors of 1.52, 1.84, and 1.14 for 6H15/2, 6H13/2, and 6H11/2 transitions. The Judd–Ofelt evaluation was made to support the experimental spectroscopic data. The CIE coordinates were traced to cool white color field with purity of 15.64–7.79% and CCT values of 5491–5437 K. The achieved excellent thermal properties, enhanced emission, and colorimetric properties, including color purity and natural daylight (cool) correlated color temperature (CCT) values, are advantageous for white solid-state lighting applications. [ABSTRACT FROM AUTHOR]

This paper presents the syntheses of SiO2 particles immobilized with Ag nanoparticles and their composite with Au. Ag nanoparticles are present on the surfaces of the SiO2 particles, and Ag+ ions are galvanically replaced with Au3+ ions. Finally, a method for maintaining the color durability and dispersibility of the Ag nanoparticles is demonstrated. The particles are primarily synthesized in three steps: In the first step, Sn2+ ions are adsorbed on the surfaces of the SiO2 particles; in the second step, Ag+ ions are added, which are reduced and simultaneously adsorbed on the surface while Sn2+ is oxidized to Sn4+; in the third step, Au3+ ions are reduced by galvanic replacement and deposited on the Ag surface. Extensive characterization using transmission electron microscopy, scanning transmission electron microscopy, ultraviolet-visible spectroscopy, and X-ray photoelectron spectroscopy reveals that the Ag–Au composite nanoparticles (17.2 ± 4.1 nm) are immobilized on the surface of the SiO2 particles (<1 µm). The morphology and coloration of the SiO2 particles with the immobilized Ag–Au composite nanoparticles remain preserved in nitric acid. This preservation is more pronounced than that observed in SiO2 particles with immobilized Ag nanoparticles. This enhanced durability can be attributed to the formation of stable bonds between Ag and Au. [ABSTRACT FROM AUTHOR]

Efficient separation of Carlin-type gold deposits is a challenge for the utilization of gold ores. The majority of gold in Carlin-type gold ores occurs as invisible gold within pyrite, resuiting in the poor crysta1lization of pyrite. The previous investigation has shown that oxidation caused the homogenization effect, thereby resuiting in adhesion, thus, deteriorafing the separation resuits of Carhn-type gold deposits. Based on the understanding of interacfions mechanssm between pyrite and dolomite,a technical prototype of "strengthening dsspersion" to opttmize the separation index of Carlintype gold deposits was preliminari1y proposed and highly selective reagents sodium amino phosphate was se!ected to realize the apphcation of the technical prototype, good separation indccators have been obtained in the laboratory. In this paper,the turbidity test was used to verify the effects of se!ected reagents on strengthening dispersion, meanwhlle, the artificial mixed ore and the real ores of high-and low-grade Carlin-type gold deposit were used to demonstrate the effect of reagent on mineral separation. The resuits showed that; sodium aminophosphate can achieve the expected goal of increasing the Fe and Au recovery in the concentrate, and decreasing the MgO floating ratio, whUe,increasing the Au enrichment ratio to about 3. 5. The above resuits show that sodium amino phosphate can improve the separation effidency between pyrite and dolomite by strengthening the dsspersion of oxidized pyrite and dolomite particles,so as to optimiie the flotation index of Carlintype gold mine. The prototype technology provides a reference for the development of effic!ent separation between pyrite and dolomite minera!s,and has the potential for popuiarizafion and apphcation. [ABSTRACT FROM AUTHOR]

Hydrometallurgical gold recovery processes play a pivotal role in the gold mining industry, contributing to more than 90% of global gold production. Among the array of techniques available, the Merrill–Crowe process, adsorption, ion exchange, and solvent extraction are central in extracting gold from leach solutions. While the Merrill–Crowe process and gold complex adsorption onto activated carbon represent historical cornerstones, their inherent limitations have prompted the emergence of more recent innovations in ion exchange and solvent extraction, offering enhanced selectivity, control, and sustainability. The evolution of modern organic chemistry has significantly influenced the progress of ion exchange technology, mainly through the introduction of advanced polymer matrix synthetic resins. At the same time, novel solvents tailored to gold complex interactions have revitalized ion exchange and solvent extraction. Introducing ionic liquids and deep eutectic solvents has also added a new dimension to efforts to improve gold extraction metallurgy. This paper reviews these cutting-edge developments and their potential to revolutionize the hydrometallurgical gold recovery process, addressing the pressing need for improved efficiency and environmental responsibility. [ABSTRACT FROM AUTHOR]

• The utilization characteristics of gold tailings were reviewed. • The recovery of valuable components from gold tailings was summarized. • The application of gold tailings in the field of materials was adumbrated. • A new process combining magnetic separation and cemented filling was proposed. Gold tailings are characterized by low-grade, complex composition, fine embedded particle size, environmental pollution, and large land occupation. This paper describes the mineralogical properties of gold tailings, including chemical composition, phase composition, particle size distribution, and microstructure; summarizes the recycling and utilization of components such as mica, feldspar, and valuable metals in gold tailings; reviews harmless treatment measures for harmful elements in gold tailings; and adumbrated the research progress of gold tailings in the application fields of building materials, ceramics, and glass materials. Based on these discussions, a new technology roadmap that combines multistage magnetic separation and cemented filling is proposed for the clean utilization of all components of gold tailings. [ABSTRACT FROM AUTHOR]

The recovery of valuable gold from wastewater is of great interest because of the widespread use of the precious metal in various fields and the pollution generated by gold-containing wastes in water. In this paper, a water-insoluble cross-linked adsorbent material (TE) based on cyanuric chloride (TCT) and ethylenediamine (EDA) was designed and used for the adsorption of Au(III) from wastewater. It was found that TE showed extremely high selectivity (D = 49,213.46) and adsorption capacity (256.19 mg/g) for Au(III) under acidic conditions. The adsorption rate remained above 90% eVen after five adsorption–desorption cycles. The adsorption process followed the pseudo-first-order kinetic model and the Freundlich isotherm model, suggesting that physical adsorption with a multilayer molecular overlay dominates. Meanwhile, the adsorption mechanism was obtained by DFT calculation and XPS analysis, and the adsorption mechanism was mainly the electrostatic interaction and electron transfer between the protonated N atoms in the adsorbent (TE) and AuCl4−, which resulted in the redox reaction. The whole adsorption process was the result of the simultaneous action of physical and chemical adsorption. In conclusion, the adsorbent material TE shows great potential for gold adsorption and recovery. [ABSTRACT FROM AUTHOR]

This article presents a study of 52 metallic artifacts made of gold and copper from the archaeological sites of Tamtoc and Rancho Aserradero, both located in the Huastec region of San Luis Potosí, Mexico. These objects served both utilitarian (e.g., needles, fish hooks, and axes) and ornamental (e.g., rings, beads, and bells) purposes. The objective of this paper is to provide a detailed description of the artifacts, present the results of an elemental, non-invasive, and non-destructive in situ analysis performed using X-ray fluorescence, reconstruct the manufacturing processes, and compare these findings with similar objects from other contemporary Mesoamerican regions. This research generated new data and knowledge about the use of metals and alloys in the Huastec region, the technological and cultural decisions behind the creation of these objects, and the exchange networks that facilitated their distribution. The examination of the 52 pieces revealed significant diversity in morphology and elemental composition, which limited the cultural interpretations due to the small sample size. Nevertheless, our results indicate that the studied sites were part of an extensive exchange network with access to metallic objects from the central and western regions of Mesoamerica, as well as Oaxaca and/or Central America. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) are present not only in the environment but also in drinking water, food, and consumer products. These MPs being toxic, carcinogenic, endocrine disrupting, and genetic risk creators cause several diseases. Despite various approaches, the development of onsite applicable, facile, and quick MP detection methods is still challenging. Here, 3D‐plasmonic gold nanopocket (3D‐PGNP) nanoarchitecture is formed on a paper substrate for simultaneous MP filtration and detection. The paper‐based 3D‐PGNP is integrated with a syringe filter device, and then, MP‐containing solutions are injected through the syringe. Subsequent detection of the MPs using the surface‐enhanced Raman scattering (SERS) successfully identifies the MPs without pretreatment. The interface and volumetric hotspot generation of 3D‐PGNP around the captured MPs significantly improves the sensitivity, which is confirmed by finite‐difference time‐domain simulation. Then, the SERS mapping images obtained from a portable Raman spectrometer are transformed into digital signals via machine learning (ML) technique to identify and quantify the MP distribution. The developed SERS‐ML‐based MP detection method is applied for mixture MPs and for real matrix samples, demonstrating that the method provides improved accuracy. This system is expected to be used for various MPs detection and for environmentally hazardous substances, such as bacteria, viruses, and fungi. [ABSTRACT FROM AUTHOR]

Thiosullate is considered to be the most promising gold extraction reagent in gold leaching process due to its advantages of non-toxicity and high efficiency. The electrochemical behavior of gold electrode in Cu2+-en-S2 O$_ gold leaching system was investigated by electrochemical testing methods (open circuit potential, cyclic voltammetry, Talel curve and electrochemical impedance). Characterization ol surlace oxidation products ol gold electrodes using Raman spectroscopy and XPS, and the oxidation mechanism ol gold was clarilied. The experimental results show that S2O32- can promote the oxidation ol the gold surface, and under the electrochemical conditions in this paper, the reaction rate is controlled by the step ol charge transfer when the gold electrode is in the 5 mmol/L Cu2+-10 mmol/L en-100 mmol/L S2O32- system. The thiosullate concentration in the system controls the dissolution ol gold by allecting its surlace properties and surlace reaction rate. The electrochemical oxidation mechanism ol gold electrodes in the Cu,十一en-S2O32- leaching gold system was this paper elucidated, and a theoretical basis was provided for the regulation ol the composition ol gold leaching reagents. [ABSTRACT FROM AUTHOR]

Abstract: Nanomaterials with unique electronic, optical and catalytic properties have recently been at the forefront of research due to their tremendous range of applications. Taking gold, silver and titania nanoparticles as examples, we have reviewed the current research works on paper functionalized by these nanoparticles. The functionalization of paper with only a very small concentration of nanoparticles is able to produce devices with excellent photocatalytic, antibacterial, anti-counterfeiting, Surface Enhanced Raman Scattering (SERS) and Surface Plasmon Resonance (SPR) performances. This review presents a brief overview of the properties of gold, silver and titania nanoparticles which contribute to the major applications of nanoparticles-functionalized paper. Different preparation methods of the nanoparticles-functionalized paper are reviewed, focusing on their ability to control the morphology and structure of paper as well as the spatial location and adsorption state of nanoparticles which are critical in achieving their optimum applications. In addition, main applications of the nanoparticles-functionalized papers are highlighted and their critical challenges are discussed, followed by perspectives on the future direction in this research field. Whilst a few studies to date have characterized the distribution of nanoparticles on paper substrates, none have yet optimized paper as a nanoparticles'' substrate. There remains a strong need to improve understanding on the optimum adsorption state of nanoparticles on paper and the heterogeneity effects of paper on the properties of these nanoparticles. [Copyright &y& Elsevier]

Abstract: SERS of C60/C70 adsorbed on gold nanoparticles coated on filter paper or filter film was studied. As a new SERS substrate, dried gold-coated filter paper or filter film has a high SERS activity, whose enhancement factor can be up to about 105, because it avoided the influence of solvents in C60/C70 solution and water in gold hydrosols. The influence of the gold thickness coated on filter paper or filter film to SERS of C60/C70 adsorbed on gold nanoparticles was mainly discussed. It is indicated that the SERS effect of C60/C70 was very sensitive to the distribution and aggregated characteristics of gold nanoparticles, and the SERS intensity of each mode increased at its own proportion, but it integrally tended to saturation when the thickness of colloidal gold coatings increased. [Copyright &y& Elsevier]

Recently a new di-gold(i) organometallic complex [1,3-(Ph3PAu)2-C6H4] (KF0101) has been synthesised and found to exhibit cytotoxic activity in vitro. Subsequently it has been demonstrated that KF0101 shows little or no cross-resistance against a number of the cisplatin resistant ovarian cancer cell lines in vitrosuggesting a different mode of action for the drug. In this study, syncrotron radiation infrared microspectroscopy (SR-IRMS) has been used on drug treated single A2780 cells in order to determine if this different mode of action can be identified spectroscopically. The aim of the study was to establish: (i) if single cell SR-IRMS could be used to give insight into the cellular response on treatment with different cytotoxic agents relative to non-treated cells (control) and (ii) that if the cytotoxic drugs elicit a different biochemical response these responses could be distinguished from each other. The most striking features obtained after Principal Componants Analysis (PCA) of Resonant Mie Scattering (RMieS) corrected single cell spectra of drug treated ovarian A2780 cells are: (i) The spectra obtained for the control are quite heterogeneous and several hundred spectra are required to adequately define the nature of the control; (ii) after drug treatment at the IC50 level for 24 h with cisplatin, KF0101, methotrexate, paclitaxel or 5-fluorouracil the cell spectra, as represented on a PCA scores plot, generally concentrate in certain well defined areas of the control, there are however a small number of spectra that fall outside of the area defined by the control; and (iii) a differentiation between cell spectra obtained on treatment with different drugs is observed which fits well with different in vitrocell culture behaviour and a flow cytometry cell cycle analysis of the contol and drug treated cells. Inspection of the loading plots shows that PC1 is essentially the same for all plots and reflects changes in cell biochemistry related to the cell cycle. PC2, however, on comparison of the control versuscisplatin or cisplatin versusKF0101 is indicative of differences induced by drug treatment and has been termed as cell cycle-plus behaviour. These data are shown to be consistent with that obtained using bench-top IRMS by averaging a number of single cell spectra and carrying out a PCA, but SR-IRMS offers more insight into how the drug is affecting the cell population. More importantly, this approach enables the influence of the cell cycle on both the control and drug treated samples to be taken into consideration when evaluating the drug–cell interaction. [ABSTRACT FROM AUTHOR]

This document is a summary of a special issue of the journal Catalysts, which focuses on the research and discoveries in gold, silver, and copper catalysis. The issue features a diverse collection of research papers that highlight the versatility and effectiveness of these metallic catalysts in various catalytic processes. The papers cover topics such as the design of new catalysts, the development of advanced photocatalysts, the use of bimetallic catalysts, the influence of shape effects on catalytic performance, and the catalytic degradation of pollutants. The papers collectively contribute to the advancement of catalysis science and provide valuable insights for researchers and practitioners in the field. [Extracted from the article]

• A fluorimetric detection of gold on microfluidic paper device was developed using a common cellphone and analysis using Photoshop software. • The new paper device was combined with fire-assay method in analysis of gold in ores. • This sensor had good LOD due to three stage pre-concentration. • New method proved to work comparable to reference assay (Fire-assay-AAS) The present study was conducted to develop a simple, low-cost and sensitive micro fluidic paper-based analytical device (µPAD) for analysis of gold in geological samples. This µPAD was fabricated employing eyeliner pencil method. It consists of different zones, including detection, pH adjustment, reaction and elution. We injected 29 µL elution solution in the center of µPAD, direct Au3+, after adjusting pH, to make it react with rhodamine B. The formation of RB-Au3+ complex led to quench of rhodamine B fluorescence. The image of each detection zone was captured using a cell phone camera under a UV lamp, and luminosity intensity was subsequently measured with Photoshop software. Various parameters were studied in order to achieve the most efficient performance of the paper sensor. Under the optimized condition, a wide linear range (1–40 mg L−1, R2 = 0.996) was obtained with detection limit of 0.15 mg L−1. Ultimately, the developed µPAD was applied for the determination of gold in ore samples. The obtained results were in good agreement with those obtained from standard method. The combination of fire assay and µPAD in the determination of gold in geological samples improved the detection limit based on enrichment factor of 75. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synergistic effects of precursors and activation agents on Au selectivity were studied. • The adsorption mechanisms were elucidated via characterization and DFT modeling. • AuCl 4 - presented most stable coordination with binding energy, E b of −4064.15 eV. • The maximum Au uptake of 1679.74 ± 37.66 mg/g was aided by partial reduction. The surging affluent in society, concomitant with increasing global demand for electrical and electronic devices, has led to a sharp rise in e-waste generation. E-wastes contain significant amounts of precious metals, such as gold, which can be recovered and reused, thus reducing the environmental impact of mining new metals. Selective recovery using sustainable and cost-effective materials and methods is therefore vital. This study undertook a detailed evaluation of low-cost biomass-derived activated carbon (AC) for selective recovery of Au from simulated e-waste streams. Utilizing high-performance synthesized H 2 SO 4 -AC, the adsorption mechanisms were explicated through a combination of characterization techniques, i.e., FE-SEM, BET, TGA, XRD, FTIR, XPS, and DFT simulations to conceptualize the atomic and molecular level interactions. Optimization of coordination geometries between model H 2 SO 4 -AC and anionic complexes revealed the most stable coordination for AuCl 4 - (binding energy, E b = -4064.15 eV). The Au selectivity was further enhanced by reduction of Au(III) to Au(0), as determined by XRD and XPS. The adsorption reaction was relatively fast (∼5h), and maximum Au uptake reached 1679.74 ± 37.66 mg/g (among highest), achieved through adsorption isotherm experiments. Furthermore, a mixture of 0.5 M thiourea/1 M HCl could effectively elute the loaded Au and regenerate the spent AC. This study presents radical attempts to examine in detail, the synergistic effects of H 2 SO 4 activation on biomass-derived ACs for selective recovery of Au from complex mixtures. The paper therefore describes a novel approach for the selective recovery of Au from e-wastes using multifunctional biomass-derived H 2 SO 4 -AC. [ABSTRACT FROM AUTHOR]

Nowadays, there is a need for new sources of noble metals due to their dwindling natural resources. This paper presents studies on the sorption of noble metals such as Au(III), Pt(IV), Pd(II) and Rh(III) from model chloride solutions on a newly prepared Amberlite XAD-16–Aliquat 336 sorbent. A "warm impregnation" method without the use of toxic organic solvents was applied to impregnate the polymer matrix. The influence of such factors as hydrochloric acid concentration, sorbent mass and phase contact time was investigated. Kinetic as well as adsorption isotherm studies were carried out. The sorption capacity of the synthesized sorbent was Au(III)—94.34 mg/g, Pt(IV)—45.35 mg/g and Pd(II)—46.03 mg/g. Based on thermodynamic considerations, their sorption proved to be endothermic, as the values of ΔH° > 0. Sorption was spontaneous and favourable (ΔG° < 0). After leaching the RAM module, there was obtained a real solution, in which the metal contents were determined: 38.10 mg/g of gold and 1.76 mg/g of palladium. Totals of 99.9% of gold and 45.4% of palladium were removed from the real leaching solution, with other elements in the solution. [ABSTRACT FROM AUTHOR]

Animal-based metal threads were largely used between the 10th and the fifteenth century, in European, Middle Eastern and Far Eastern textile productions for the decoration of textiles and cloths. They belong to a larger group of metal threads, used either as flat threads or wrapped around a fiber core, that were backed by an organic support (animal or paper). This study focuses on the medieval production of metal threads backed by an animal membrane (e.g. gut membrane), or skin. A total of 91 samples were collected from a corpus of 66 textile fragments belonging to 54 catalogued objects. The relevance and novelty of the present study is represented by the combination of proteomics, cross-section analysis, and scanning electron microscopy (SEM–EDS and SEM-µXRF). The diversity of materials and manufacturing techniques found within each typology of thread, respectively, membrane-based metal threads and skin-based metal threads, hinted at different production technologies. Membrane-based threads were found to be invariably made from cattle gut membrane, coated with gilt-silver leaves. A possible sheep glue adhesive was found in a few samples. Skin-based threads were made from either goat or sheep leather, coated with metal leaves or powder. Within the three different types of coatings identified (silver, gold and gilt-silver), gold coatings were the most represented. Goat leather threads were associated with an egg-white binder, while sturgeon glue was identified as adhesive in all sheep leather threads. Collagen glue from other species (cattle, sheep, horse) was occasionally found in mixed adhesives. In two textiles, the finding of human proteins indicates past contamination due to handling or use. The analytical results show coherence between the fabrication patterns of animal-based metal threads and their probable geographical areas of manufacture, indicating that the study of materials and techniques provide further criteria to classify and group textiles, and trace correlations between manufacturing centers within Eurasian territories. [ABSTRACT FROM AUTHOR]

Tajikistan possesses large reserves of dump tailings characterized by a high gold content. The formation of these dump tailings is associated with the low cost of gold in the past, since rich ores with a gold content above 6–8 g/t were more often involved in processing. At recovery of ≈ 70–75%, tailings with a gold content below 1.8 g/t were disposed of. The paper studies the material composition and carries out an assessment of the degree of refractoriness of the studied dump tailings to leaching. It was established that the main components of tailings are SiO2 and Al2O3. The dump tailings contain 2.4 g/t of gold and 7 g/t of silver. In terms of material composition, the sample of the dump tailings belongs to a readily cyanidable type. Gold finely disseminated in acid-soluble minerals represents 6–6.5%, while minerals insoluble in acids and quartz contain 15% of gold. In addition, the tailing sample contains gold encapsulated in minerals soluble in sulfuric acid. In terms of gold form, the dump tailings are classified as medium refractory to leaching processes. The diagnostic leaching test results for gold showed that the use of thiourea as a lixivant in the further development of the leaching process is promising. Gold recovery by thiourea leaching was 78%. [ABSTRACT FROM AUTHOR]

The synthesis of gold(III) and gold(I)–gold(III) complexes with phosphide bridges is still a matter that requires solutions for their marked instability, in spite of the affinity of this metal in both oxidation states for phosphorous donor ligands. In the course of our studies, we realized that the presence of perhalophenyl groups of the type pentafluorophenyl or 3,5-dichlorotrifluorophenyl in the complexes gives rise to an increase in their stability that eases their isolation and structural characterization. In this paper, we describe two new fully characterized neutral compounds of this type to extend the knowledge on this family of compounds, [{Au(C6Cl2F3)2}2(µ-PPh2)2] (1) and [{Au(C6Cl2F3)2(µ-PPh2)2Au}2] (2). In this work, we analyze the role of the perhalophenyl groups in the stability of these complexes by using quantum chemical topology methodologies, specifically employing an analysis of the non-covalent interactions (NCIs) in real space and evaluating the electrostatic potential surfaces (ESP). Our findings reveal the existence of appreciable π-stacking interactions among the perhalophenyl and phenyl groups in both compounds, significantly contributing to the stability of the systems. [ABSTRACT FROM AUTHOR]

Plenty of gold deposits related to Late Mesozoic craton destruction are widely distributed in eastern North China Craton. However, significant differences in research degrees, ore-forming characteristics, and proven reserves exist among different regions in the North China Craton. The Liaodong Peninsula has similar regional geological characteristics to those of the Jiaodong Peninsula, with both experiencing craton destruction during Late Mesozoic, but the two areas have substantial differences in terms of gold mineralization and the proven gold resources. Based on regional geology, Mesozoic magmatic-tectonic evolution and ore geology, combined with integrated geophysical exploration and big data AI resource prediction, in this paper, we propose that the ore-forming materials of Late Mesozoic gold deposits in Liaodong were mainly originated from mantle-derived melts and/or fluids induced by craton destruction. The gold deposits were primarily controlled by NE-NNE-trending faults, mainly classified as fracture-controlled altered rock-type and sulfide-bearing quartz vein-type. Moreover, our study predicts that the Yalu River fault zone and its related secondary faults, as well as the periphery and deeper parts of known goldfields, are the important regions for future gold resource exploration. The Yalu River metallogenic belt has an enormous potential for gold resources, and the Liaodong Peninsula has a potential to add thousands of tons of gold resources. [ABSTRACT FROM AUTHOR]

Fluctuation-induced forces are a hallmark of the interplay between fluctuations and geometry. We recently proved the existence of a multi-parametric family of exact representations of Casimir and Casimir–Polder interactions between bodies of arbitrary shape and material composition, admitting a multiple scattering expansion (MSE) as a sequence of inter-body and intra-body multiple wave scatterings. The approach requires no knowledge of the scattering amplitude (T-matrix) of the bodies. In this paper, we investigate the convergence properties of the MSE for the Casimir–Polder interaction of a polarizable particle with a macroscopic body. We consider representative materials from different classes, such as insulators, conductors, and semiconductors. Using a sphere and a cylinder as benchmarks, we demonstrate that the MSE can be used to efficiently and accurately compute the Casimir–Polder interaction for bodies with smooth surfaces. [ABSTRACT FROM AUTHOR]