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Camouflage skills are important for understanding the relationship between predators and prey in ecological systems. Mimicry is a common strategy used by creatures to alter their appearance in order to blend in with their surroundings and avoid detection. This paper unveils a previously unknown camouflage strategy that creates false object information and positions of an object in the visual range of radar sensor vision. A dispersion‐modulated illusionary metasurface to realize focal spot coding in a 3‐dimensional space to fit the radar imaging process is proposed. As the radar image indicates, an aircraft image is created by a flat metasurface plane with good polarization adaptation ability. Design, simulation, and experimental results validate the study. This camouflage strategy indicates the complexity of the food chain and can be used by both predators and prey, providing accessible insights for maintaining biological diversity. The metasurface‐based system can be potentially utilized in future radar markers for marine traffic control systems. [ABSTRACT FROM AUTHOR]

In this study, two new laboratory reference solutions for testing Cu isotopic composition were established and investigated. Two commercially available pure copper products, copper plate and copper wire, were dissolved in 1000-ml Teflon® bottles, to produce 200 μg ml−1 stock solutions (hereafter referred to as NWU-Cu-A and NWU-Cu-B), and cryogenically stored. The Cu isotopic compositions of the two samples were determined in three different laboratories using multi-collector inductively coupled plasma-mass spectrometry, and the Cu isotopic compositions obtained from the standard-sample bracketing method were consistent within the two standard deviation (2 s) range. The Cu isotopic compositions of the NWU-Cu-A and NWU-Cu-B standard solutions were δ65Cu = +0.91 ± 0.03‰ (2 s, n = 42) and δ65Cu = −0.05 ±0.03‰ (2 s, n = 49), respectively, relative to the reference material NIST SRM 976. [ABSTRACT FROM AUTHOR]

A new matrix‐matched reference material (NWU‐Brt) with sulfur isotope ratios resembling those of natural barites has been developed for in situ S isotope measurements by laser ablation multi‐collector inductively coupled plasma‐mass spectrometry (LA‐MC‐ICP‐MS). A 100 g quantity of natural barite crystal was milled to ultra‐fine particles and sintered to a solid block using a fast hot‐pressing sintering technique (FHPS). We report δ34S ratios determined by isotope ratio mass spectrometry (IRMS), solution nebuliser multi‐collector inductively coupled plasma‐mass spectrometry (SN‐MC‐ICP‐MS) and LA‐MC‐ICP‐MS, involving up to six participating laboratories. The homogeneity of δ34S ratios of the synthesised barite was tested by LA‐MC‐ICP‐MS with an analytical spot size of 53 μm. The LA‐MC‐ICP‐MS results show that NWU‐Brt demonstrates a satisfactory homogeneous composition and is an appropriate material for calibrating δ34S ratios in barite. IRMS and SN‐MC‐ICP‐MS produced mean δ34S values of +14.17 ± 0.42‰ (2s) and +14.27 ± 0.23‰ (2s), respectively. The results of LA‐MC‐ICP‐MS analyses are consistent with the IRMS and SN‐MC‐ICP‐MS ratios within uncertainty. Overall, our results confirm the suitability of NWU‐Brt for the calibration of δ34S ratios in barite using LA‐MC‐ICP‐MS. [ABSTRACT FROM AUTHOR]

The Liziyuan gold deposit, situated on the south side of the Shangdan suture zone, West Qinling Orogen, occurs in metamorphic volcanic rocks (greenschist facies) of the early Paleozoic Liziyuan Group and in Indosinian Tianzishan monzogranite. Orebodies in the Liziyuan gold field are controlled by the ductile‐brittle shear zone, and by thrusting nappe faults related to the Indosinian orogeny. In detail, this paper analyzed the geological characteristics of the Liziyuan gold field, and the Pb isotopes of the Lziyuan host rocks, granitoids (Tianzishan monzogranite and Jiancaowan syenite porphyry), sulfides, and auriferous quartz veins by multiple‐collector inductively coupled plasma mass spectrometry (MC–ICP–MS). In addition, previous data on the sulfur, hydrogen, and oxygen isotopes were employed to discuss the possible sources of the ore‐forming fluids and materials, and to further understand the tectonic setting of the Liziyuan gold deposit. The sulfides and their host rocks (Lziyuan Group), Tianzishan monzogranite and Jiancaowan syenite porphyry, and auriferous quartz veins have similar Pb isotopic compositions. Zartman's plumbotectonic model diagram shows that most of the data for the deposit fall near the orogenic Pb evolutionary curve or within the area between the orogenic and mantle Pb evolutionary curves. In the Δβ‐Δγ diagram, which genetically classifies the lead isotopes, most of the data fall within the range of the subduction‐zone lead mixed with upper crust and mantle. This indicates that a complex source of the ore lead formed in the orogenic environment. The δ34S values of the sulfides range from 3.90 to 8.50‰ (average 6.80‰), with a pronounced mode at 5.00‰–8.00‰. These values are consistent with that of orogenic gold deposits worldwide, indicating that the sulfur sourced mainly from reduced metamorphic fluids. The isotopic hydrogen and oxygen compositions support a predominantly metamorphic origin of the ore‐forming fluids, with possible mixing of minor magmatic fluids, but the late stage was dominated by meteoric water. The characteristics of the Liziyuan gold deposit formed in the Indosinian orogenic environment of the Qinling Orogen are consistent with those of orogenic gold deposits found worldwide. [ABSTRACT FROM AUTHOR]

The sulfur isotope system is important in tracing a variety of geochemical processes. However, the availability of matrix‐matched reference materials for in situ sulfur isotope ratio measurement is limited. This study analysed four sulfide specimens to investigate their potential as reference materials for in situ sulfur isotope determination, including three natural sulfide minerals (sphalerite SPH‐1, chalcopyrite GC‐1 and galena NWU‐GN), and one resin preserved pyrite powder (RPPY). These four sulfides were analysed independently in four laboratories using both bulk and microbeam analysis techniques, all of which gave equivalent results within uncertainty with comparable accuracy and precision. The sulfur isotopes of these four sulfides are homogeneous based on a large number of isotope determinations by solution nebulisation multi‐collector inductively coupled plasma‐mass spectrometry (MC‐ICP‐MS) and laser ablation (LA) MC‐ICP‐MS. The mean δ34S values for SPH‐1, RPPY, GC‐1 and NWU‐GN determined by gas source isotope ratio mass spectrometry (GS‐IRMS) and solution nebulisation MC‐ICP‐MS are −7.13 ± 0.41‰ (2s), 3.66 ± 0.24‰ (2s), −0.65 ± 0.28‰ (2s), 28.21 ± 0.17‰ (2s) relative to the Vienna‐Canyon Diablo troilite (V‐CDT) reference value, respectively, and which are proposed as potential preferred values. Over 400 spot analyses performed on randomly selected fragments of each sulfide by LA‐MC‐ICP‐MS yielded highly consistent δ34S values with the preferred values. Thus, SPH‐1, GC‐1, NWU‐GN and RPPY are considered a set of candidate matrix‐matched sulfide reference materials for in situ sulfur isotope determination. [ABSTRACT FROM AUTHOR]

This study examined the micro‐homogeneity of zinc isotope composition of the NIST SRM 683 and NBS 123 reference materials using femtosecond laser ablation multi‐collector inductively coupled plasma‐mass spectrometry (fsLA‐MC‐ICP‐MS). NIST SRM 683 and NBS 123 are homogeneous in Zn isotope composition based on numerous measurements performed on twenty chips and four mounts of sphalerite using solution nebulisation (SN)‐MC‐ICP‐MS and fsLA‐MC‐ICP‐MS. The mean δ66ZnJMC‐Lyon values of NIST SRM 683 and NBS 123 determined by SN‐MC‐ICP‐MS were 0.11 ± 0.02‰ (2 standard deviation (2s), n = 100) and 0.16 ± 0.02‰ (2s, n = 62), respectively. The mean δ66ZnJMC‐Lyon values determined by fsLA‐MC‐ICP‐MS analyses for NIST SRM 683 and NBS 123 were 0.12 ± 0.05‰ (2s, n = 200) and 0.16 ± 0.05‰ (2s, n = 212), consistent with the bulk isotope compositions within uncertainty. The in situ measurement precision for NIST SRM 683 and NBS 123 was better than 0.06‰ (2s), suggesting NIST SRM 683 and NBS 123 are suitable to serve as microanalytical reference materials for Zn isotope measurement. Zinc isotopic compositions of Zn‐rich materials were also determined using fsLA‐MC‐ICP‐MS under wet/dry plasma conditions. Their δ66ZnJMC‐Lyon values were in agreement with those obtained by SN‐MC‐ICP‐MS analysis, suggesting that fsLA‐MC‐ICP‐MS is suitable to measure Zn isotopic ratios in Zn‐rich materials. Thus, this method could potentially analyse spatially resolved Zn isotope compositions at the mineral or even sub‐mineral scale, such as to address the process of ore formation or Zn redistribution in near‐surface environments. [ABSTRACT FROM AUTHOR]

A new natural chalcopyrite reference material TC1725 is prepared for in situ Cu isotope measurement by femtosecond laser ablation multi‐collector inductively coupled plasma‐mass spectrometry (fsLA‐MC‐ICP‐MS). Detailed textural examination and major element determination suggest the TC1725 chalcopyrite grains have no growth rim or zoning. The chalcopyrite grain is homogeneous with respect to Cu isotopes based on a large number of measurements performed by bulk solution nebuliser (SN)‐MC‐ICP‐MS, single‐grain SN‐MC‐ICP‐MS and fsLA‐MC‐ICP‐MS. The traditional bulk isotope analyses by SN‐MC‐ICP‐MS yielded a mean δ65Cu value of −0.06 ± 0.03‰ (2s, n = 132). Randomly selected single chalcopyrite grain of TC1725 determined by SN‐MC‐ICP‐MS without column chromatography gave a mean δ65Cu value of −0.06 ± 0.04‰ (2s, n = 188). The intermediate measurement precision for four measurement sessions was better than 0.04‰ (2s), suggesting TC1725 chalcopyrite is suitable as a microanalysis reference material for Cu isotope measurement. The mean δ65Cu value determined by fsLA‐MC‐ICP‐MS analyses on different individual chalcopyrite mounts and strips was −0.06 ± 0.03‰ (2s, n = 393), consistent with the bulk isotope composition within uncertainty. The recommended mean δ65Cu value for this chalcopyrite reference material is −0.06 ± 0.03‰ (2s, n = 132) as determined by bulk SN‐MC‐ICP‐MS. [ABSTRACT FROM AUTHOR]