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Abstract Hydrogenation is a versatile chemical process with significant applications in various industries, including food production, petrochemical refining, pharmaceuticals, and hydrogen carriers/safety. Traditional hydrogenation of aromatics, hindered by the stable π-conjugated phenyl ring structures, typically requires high temperatures and pressures, making ambient hydrogenation a grand challenge. Herein, we introduce a PdPtRuCuNi high entropy alloy (HEA) nanocatalyst, achieving an exceptional 100% hydrogenation of carbon-carbon unsaturated bonds, including alkynyl and phenyl groups, in solid 1,4-bis(phenylethynyl)benzene (DEB) at 25 °C under ≤1 bar H2 and solventless condition. This results in a threefold higher hydrogen uptake for DEB-contained composites compared to conventional Pd catalysts, which can only hydrogenate the alkynyl groups with a ~ 27% conversion of DEB. Our experimental results, complemented by theoretical calculations, reveal that PdPtRu alloy is highly active and crucial in enabling the hydrogenation of phenyl groups, while all five elements work synergistically to regulate the reaction rate. Remarkably, this newly developed catalyst also achieves nearly 100% reactivity for ambient hydrogenation of a broad range of aromatics, suggesting its universal effectiveness. Our research uncovers a novel material platform and catalyst design principle for efficient and general hydrogenation. The multi-element synergy in HEA also promises unique catalytic behaviors beyond hydrogenation applications.

The ultimate goal of the hydrogen economy is to develop an efficient and cost-effective electrocatalyst that can accelerate hydrogen synthesis from water without or with little additional energy. This study describes a unique surface modified electrodeposited nano-sized tungsten oxide (WO3) as an intriguing bi-functional electrocatalyst for OER in alkaline and HER in acidic conditions. The nano-WO3 was synthesized hydrothermally and electrodeposited on a fluorinated tin oxide (FTO) electrode. The highly uniform distribution of the WO3@FTO catalyst results in negligible charge transfer resistance, a large electroactive surface area, and increased water-splitting potential. During oxygen evolution reaction (OER), electrodeposited WO3@FTO initiates water splitting at an overpotential (η) of just 240 mV and represents a turnover frequency (TOF) of 0.59 sec−1. These results are comparable to previously reported electrocatalysts. Under an alkaline electrolyte, a current density of 15 mA/cm2 remained constant for several hours, indicating the high stability and durability of the electrodeposited WO3@FTO electrode. The electrode also performed well in hydrogen evolution reactions (HER). A Tafel slope of 46 mV/dec and −28 mV/dec was found for OER and HER, respectively, indicating an enhanced kinetics rate of reaction taking place at the electrode surface. Furthermore, in acidic conditions, the electrode represents a lower HER overpotential of 104 mV. The work provides a significant understanding of electrodeposited WO3@FTO electrodes and their role in electrochemical water splitting.

To avoid sintering and carbon deposition of conventionally loaded catalysts, a spatial confinement strategy was employed to design a high-performance catalyst for the dry reforming of methane (DRM) reaction. With tri-metallic Ni-Co-Mg metal-organic framework (MOF-74) as a precursor, a novel nanostructured NiCoMg@C catalyst was synthesized, where the active metals Ni and Co were confined within the carbon framework derived from MOF pyrolysis. Characterization results indicate that the catalyst synthesized with MOF as template has a high specific surface area, well-dispersed metals, and strong metal-support interactions. The introduction of a high content of Mg promoted the dispersion of active metal Ni and Co and increased the number and strength of surface basic sites. Among the catalysts, NiCoMg20@C exhibited optimal catalytic activity, with initial CH4 and CO2 conversion rates reaching 75.13 % and 85.29 %, respectively. More importantly, the catalyst showed high stability during 100 h DRM reaction at 700 °C without significant carbon deposition. This research provides a new perspective for the development of DRM catalysts.

In response to the current energy and environmental challenges, reducing or replacing reliance on fossil fuels and striving for carbon neutrality seems to be the only viable choice. Recently, a cutting-edge, eco-friendly method of chemical synthesis via transient Joule heating (JH) demonstrated significant promise across various domains, including methane reforming, ammonia synthesis, volatile organic compounds removal, plastic recycling, the synthesis of functional carbon materials from repurposed solid waste, etc. In this review, the advantages, and latest developments in thermochemical synthesis by flash and transient JH are comprehensively outlined. Unlike the ongoing heating process of conventional furnaces that consume fossil fuels, dynamic and transient JH can get significantly higher reaction rates, energy efficiency, flexibility, and versatility. Subsequently, the transient reaction mechanism, data science optimization, and scale-up production models are discussed, and prospects for the integration of the electrified chemical industry with renewable energy for carbon neutrality and long-term energy storage are also envisioned.

Abstract Continuous industrialization and other human activities have led to severe water quality deterioration by harmful pollutants. Achieving robust and high-throughput water purification is challenging due to the coupling between mechanical strength, mass transportation and catalytic efficiency. Here, a structure-function integrated system is developed by Douglas fir wood-inspired metamaterial catalysts featuring overlapping microlattices with bimodal pores to decouple the mechanical, transport and catalytic performances. The metamaterial catalyst is prepared by metal 3D printing (316 L stainless steel, mainly Fe) and electrochemically decorated with Co to further boost catalytic functionality. Combining the flexibility of 3D printing and theoretical simulation, the metamaterial catalyst demonstrates a wide range of mechanical-transport-catalysis capabilities while a 70% overlap rate has 3X more strength and surface area per unit volume, and 4X normalized reaction kinetics than those of traditional microlattices. This work demonstrates the rational and harmonious integration of structural and functional design in robust and high throughput water purification, and can inspire the development of various flow catalysts, flow batteries, and functional 3D-printed materials.

Abstract Supported metal catalysts often suffer from rapid degradation under harsh conditions due to material failure and weak metal-support interaction. Here we propose using reductive hydrogenated borophene to in-situ synthesize Pt/B/C catalysts with small sizes (~2.5 nm), high-density dispersion (up to 80 wt%Pt), and promising stability, originating from forming Pt-B bond which are theoretically ~5× stronger than Pt-C. Based on the Pt/B/C module, a series (~18 kinds) of carbon supported binary, ternary, quaternary, and quinary Pt intermetallic compound nanocatalysts with sub-4 nm size are synthesized. Thanks to the stable intermetallics and strong metal-support interaction, annealing at 1000 °C does not cause those nanoparticles sintering. They also show much improved activity and stability in electrocatalytic oxygen reduction reaction. Therefore, by introducing the boron chemistry, the hydrogenated borophene derived multielement catalysts enable the synergy of small size, high loading, stable anchoring, and flexible compositions, thus demonstrating high versatility toward efficient and durable catalysis.

Abstract The recycling of spent batteries has become increasingly important owing to their wide applications, abundant raw material supply, and sustainable development. Compared with the degraded cathode, spent anode graphite often has a relatively intact structure with few defects after long cycling. Yet, most spent graphite is simply burned or discarded due to its limited value and inferior performance on using conventional recycling methods that are complex, have low efficiency, and fail in performance restoration. Herein, we propose a fast, efficient, and “intelligent” strategy to regenerate and upcycle spent graphite based on defect‐driven targeted remediation. Using Sn as a nanoscale healant, we used rapid heating (~50 ms) to enable dynamic Sn droplets to automatically nucleate around the surface defects on the graphite upon cooling owing to strong binding to the defects (~5.84 eV/atom), thus simultaneously achieving Sn dispersion and graphite remediation. As a result, the regenerated graphite showed enhanced capacity and cycle stability (458.9 mAh g−1 at 0.2 A g−1 after 100 cycles), superior to those of commercial graphite. Benefiting from the self‐adaption of Sn dispersion, spent graphite with different degrees of defects can be regenerated to similar structures and performance. EverBatt analysis indicates that targeted regeneration and upcycling have significantly lower energy consumption (~99% reduction) and near‐zero CO2 emission, and yield much higher profit than hydrometallurgy, which opens a new avenue for direct upcycling of spend graphite in an efficient, green, and profitable manner for sustainable battery manufacture.

Biomimetic metallic biomaterials prepared for bone scaffolds have drawn more and more attention in recent years. However, the topological design of scaffolds is critical to cater to multi-physical requirements for efficient cell seeding and bone regeneration, yet remains a big scientific challenge owing to the coupling of mechanical and mass-transport properties in conventional scaffolds that lead to poor control towards favorable modulus and permeability combinations. Herein, inspired by the microstructure of natural sea urchin spines, biomimetic scaffolds constructed by pentamode metamaterials (PMs) with hierarchical structural tunability were additively manufactured via selective laser melting. The mechanical and mass-transport properties of scaffolds could be simultaneously tuned by the graded porosity (B/T ratio) and the tapering level (D/d ratio). Compared with traditional metallic biomaterials, our biomimetic PM scaffolds possess graded pore distribution, suitable strength, and significant improvements to cell seeding efficiency, permeability, and impact-tolerant capacity, and they also promote in vivo osteogenesis, indicating promising application for cell proliferation and bone regeneration using a structural innovation.

Abstract Carbon-supported nanoparticles are indispensable to enabling new energy technologies such as metal-air batteries and catalytic water splitting. However, achieving ultrasmall and high-density nanoparticles (optimal catalysts) faces fundamental challenges of their strong tendency toward coarsening and agglomeration. Herein, we report a general and efficient synthesis of high-density and ultrasmall nanoparticles uniformly dispersed on two-dimensional porous carbon. This is achieved through direct carbothermal shock pyrolysis of metal-ligand precursors in just ~100 ms, the fastest among reported syntheses. Our results show that the in situ metal-ligand coordination (e.g., N → Co2+) and local ordering during millisecond-scale pyrolysis play a crucial role in kinetically dominated fabrication and stabilization of high-density nanoparticles on two-dimensional porous carbon films. The as-obtained samples exhibit excellent activity and stability as bifunctional catalysts in oxygen redox reactions. Considering the huge flexibility in coordinated precursors design, diversified single and multielement nanoparticles (M = Fe, Co, Ni, Cu, Cr, Mn, Ag, etc) were generally fabricated, even in systems well beyond traditional crystalline coordination chemistry. Our method allows for the transient and general synthesis of well-dispersed nanoparticles with great simplicity and versatility for various application schemes.

Abstract High‐entropy alloys (HEAs) have attracted widespread attention as both structural and functional materials owing to their huge multielement composition space and unique high‐entropy mixing structure. Recently, emerging HEAs, either in nano or highly porous bulk forms, are developed and utilized for various catalytic and clean energy applications with superior activity and remarkable durability. Being catalysts, HEAs possess some unique advantages, including (1) a multielement composition space for the discovery of new catalysts and fine‐tuning of surface adsorption (i.e., activity and selectivity), (2) diverse active sites derived from the random multielement mixing that are especially suitable for multistep catalysis, and (3) a high‐entropy stabilized structure that improves the structural durability in harsh catalytic environments. Benefited from these inherent advantages, HEA catalysts have demonstrated superior catalytic performances and are promising for complex carbon (C) and nitrogen (N) cycle reactions featuring multistep reaction pathways and many different intermediates. However, the design, synthesis, characterization, and understanding of HEA catalysts for C‐ and N‐involved reactions are extremely challenging because of both complex high‐entropy materials and complex reactions. In this review, we present the recent development of HEA catalysts, particularly on their innovative and extensive syntheses, advanced (in situ) characterizations, and applications in complex C and N looping reactions, aiming to provide a focused view on how to utilize intrinsically complex catalysts for these important and complex reactions. In the end, remaining challenges and future directions are proposed to guide the development and application of HEA catalysts for highly efficient energy storage and chemical conversion toward carbon neutrality.

Battery recycling is indispensable for alleviating critical material shortages and enabling sustainable battery applications. However, current methods mostly focus on spent batteries, which not only require sophisticated disassembly and material extraction but also have unknown chemistries and states of health, resulting in high costs and extreme challenges to achieve regeneration. Here, we propose the direct recycling and effective regeneration of air-degraded LiNi0.5Co0.2Mn0.3O2 (NCM523) cathode directly from battery scraps generated during battery manufacturing. The NCM523 shows surface degradation only a few nanometers deep and accordingly can be regenerated without adding Li, achieving restored properties (170 mAh g−1 at 0.1 C, 92.7% retention after 1000 cycles) similar to those of fresh commercial materials. EverBatt analysis shows that scrap recycling has a profit of $1.984 ​kg−1, which is ∼10 times higher than conventional recycling, making it practical and economical to rejuvenate slightly degraded electrode materials for sustainable battery manufacturing.

Abstract Although Pt and other noble metals are the state‐of‐the‐art catalysts for various energy conversion applications, their low reserve, high cost, and instability limit their large‐scale utilization. Herein, we report a hybrid catalysts design featuring noble metal clusters (e.g., Pt) uniformly dispersed and stabilized on high‐entropy alloy nanoparticles (HEA, e.g., FeCoNiCu), denoted as HEA@Pt, which is prepared via ultra‐fast shock synthesis (∼300 ms) for HEA alloying combined with Pt galvanic replacement for surface anchoring. In our design, the HEA core critically ensures high dispersity, stability, and tunability of the surface Pt clusters through high entropy stabilization and core‐shell interactions. As an example in the hydrogen evolution reaction, HEA@Pt achieved a significant mass activity of 235 A/gPt, which is 9.4, 3.6, and 1.9‐times higher compared to that of homogeneous FeCoNiCuPt (HEA‐Pt), Pt, and commercial Pt/C, respectively. We also demonstrated noble Ir stabilized on FeCoNiCrMn nanoparticles (HEA‐5@Ir), achieving excellent anodic oxygen evolution performance and highly efficient overall water splitting when combined with the cathodic HEA@Pt. Therefore, our work developed a general catalysts design strategies by using high entropy nanoparticles for effective dispersion, stabilization, and modulation of surface active sites, achieving a harmonious combination of high activity, stability, and low cost.

Metal nanoparticle-decorated carbon supports are vital for many applications, ranging from energy storage and catalysis to filtration and environmental remedies. Here, using real-time electron microscopy of a single carbon nanofiber during Joule heating, the authors report atomistic mechanisms responsible for nucleation and stabilization of nanoparticles on amorphous carbon supports.

Metal corrosion leads to serious resource waste and economic losses, and in severe cases, it can result in catastrophic safety incidents. As a result, proper coatings are often employed to separate metal alloys from the ambient environment and thus prevent or at least slow down corrosion. Among various materials, high-entropy alloy coatings (HEA coating) have recently received a lot of attention due to their unique entropy-stabilized structure, superior physical and chemical properties, and often excellent corrosion resistance. To address the recent developments and remaining issues in HEA coatings, this paper reviews the primary fabrication methods and various elemental compositions in HEA coatings and highlights their effects on corrosion resistance properties. It is found that FeCoCrNi-based and refractory high-entropy alloy coatings prepared by the laser/plasma cladding method typically show better corrosion resistance. It also briefly discusses the future directions toward high-performing corrosion-resistant coatings based on HEA design.

The performance of iron-rich calcium sulfoaluminate (IR-CSA) cement is greatly affected by mineral composition and mineral activity in the clinker. This study aims to identify the effect of CaO sources, either CaCO3 or CaSO4, on the phase formation and mineral composition of the IR-CSA clinker. Targeted samples were prepared with different proportions of CaCO3 and CaSO4 as CaO sources at 1300 °C for 45 min. Multiple methods were used to identify the mineralogical conditions. The results indicate that the mineral composition and performance of the IR-CSA clinker could be optimized by adjusting the CaO source. Both Al2O3 and Fe2O3 tend to incorporate into C4A3−xFxS¯ with an increase in CaSO4 as a CaO source, which leads to an increased content of C4A3−xFxS¯ but a decreased ferrite phase. In addition, clinkers prepared with CaSO4 as a CaO source showed much higher x value in C4A3−xFxS¯ and higher compressive strength than clinker prepared with CaCO3 as the sole CaO source. The crystal types of both C4A3−xFxS¯ and C2S were also affected, but showed different trends with the transition of the CaO source. The findings provide a possible method to produce IR-CSA cement at a low cost through cooperative utilization of waste gypsum and iron-bearing industrial solid wastes.

Alloys are important materials for catalysis but are usually limited by miscibility gaps present in their phase diagrams. Here the authors break this limitation by developing high-entropy alloy catalysts made of five earth-abundant elements and demonstrate great catalytic enhancements for ammonia decomposition.

The preparation of high-performance green cementitious material from industrial solid waste is a feasible large-scale utilization approach for industrial solid waste. This work investigates the feasibility of using industrial solid wastes in a sulphoaluminate–magnesium–potassium–phosphate cementitious composite material (SAC-MKPC) clinker preparation and the influence of the calcination temperature and clinker ingredients on the hydration behavior and mechanisms of the SAC-MKPC with a Mg/P ratio of 5. The results show that the novel SAC-MKPC that was prepared from aluminum slag, carbide slag, coal gangue, and magnesium desulfurization slag was composed mainly of mineral MgO, C4A3S¯, and C2S and the calcination temperature of the main mineral phases was 1250–1350 °C. The solid-waste-based SAC-MKPC had better mechanical properties and excellent water resistance compared with the MKPC. The optimal compressive strength reached 35.2, 70.9, 84.1, 87.7, and 101.6 MPa at 2 h, 1 d, 3 d, 7 d, and 28 d of hydration, respectively. The X-ray diffraction spectra and scanning electron micrographs of the hydration products of the SAC-MKPC clinker showed that AFt and K-struvite crystals coexisted and adhered to form a dense structure. This work provides an innovative idea to produce green cementitious material using industrial solid wastes and may promote the sustainable development of the power and mining industries.

At the molecular level, biological activities involve the transport of ions in a system. Here the authors demonstrate an ‘electron battery’ by inverting the configuration of a traditional Li-ion battery to generate an ionic current to interact with a biosystem for potential biomedical applications.

Recurrent pregnancy loss (RPL) is an important complication in reproductive health. About 50% of RPL cases are unexplained, and understanding the genetic basis is essential for its diagnosis and prognosis. Herein, we report causal KH domain containing 3 like (KHDC3L) mutations in RPL. KHDC3L is expressed in human epiblast cells and ensures their genome stability and viability. Mechanistically, KHDC3L binds to poly(ADP-ribose) polymerase 1 (PARP1) to stimulate its activity. In response to DNA damage, KHDC3L also localizes to DNA damage sites and facilitates homologous recombination (HR)-mediated DNA repair. KHDC3L dysfunction causes PARP1 inhibition and HR repair deficiency, which is synthetically lethal. Notably, we identified two critical residues, Thr145 and Thr156, whose phosphorylation by Ataxia-telangiectasia mutated (ATM) is essential for KHDC3L's functions. Importantly, two deletions of KHDC3L (p.E150_V160del and p.E150_V172del) were detected in female RPL patients, both of which harbor a common loss of Thr156 and are impaired in PARP1 activation and HR repair. In summary, our study reveals both KHDC3L as a new RPL risk gene and its critical function in DNA damage repair pathways.

Nanoparticles of non-noble metals are useful for many applications but can be prone to sintering or surface oxidation. Here, the authors use a rapid heating-cooling approach to synthesize uniformly distributed nanoparticles in a reduced graphene oxide matrix, and test them as switchable energetic materials.

Background/Aims: Oxidized low-density lipoprotein (Ox-LDL) induces macrophage proliferation, a key physiological process which leads to atherosclerosis. The aim of this study was to determine the effects of dopamine D1-like receptors on macrophage proliferation induced by Ox-LDL. Methods: The expression of dopamine D1-like receptors was determined by immunohistochemistry, reverse transcriptase-polymerase chain reaction (RT-PCR) and immunoblotting. The effect of D1-like receptors on macrophage proliferation induced by Ox-LDL was measured by 3[H]-thymidine incorporation and cell number count. Results: Dopamine D1-like receptors were present in macrophages as determined by immunohistochemistry, RT-PCR and immunoblotting. A D1-like receptor agonist, fenoldopam, which by itself had no effect on macrophage proliferation, inhibited the stimulatory effect of Ox-LDL on macrophage proliferation. This was further confirmed by the D1-like receptor antagonist SCH 23390 blocking the effect of fenoldopam, thereby indicating that the fenoldopam action was receptor specific. Phosphatidylinositol 3-kinase (PI3K/Akt) and mitogen-activated protein kinase (MAPK/ERK) pathways were also involved in the proliferative effect of Ox-LDL because in the presence of PI3K/Akt or MAPK/ERK inhibitors, LY294002 or PD98059, the stimulatory effects of Ox-LDL were blocked. Moreover, the stimulatory effect of Ox-LDL on the phosphorylation of ERK and Akt was significantly reduced by fenoldopam in macrophages. Additional experiments found that both D1 and D5 receptor expression was lower in the peritoneal macrophages from Apolipoprotein E-deficient mice compared to the control C57Bl/6J mice. Conclusions: Macrophages express D1-like receptors. The activation of the D1-like receptors significantly inhibits Ox-LDL-induced macrophage proliferation, possibly through the inhibition of the PI3K/Akt and MAPK/ERK signaling pathways.

Carbonaceous materials, such as graphite, carbon nanotubes (CNTs), and graphene, are in high demand for a broad range of applications, including batteries, capacitors, and composite materials. Studies on the transformation between different types of carbon, especially from abundant and low-cost carbon to high-end carbon allotropes, have received surging interest. Here, we report that, without a catalyst or an external carbon source, biomass-derived amorphous carbon and defective reduced graphene oxide (RGO) can be quickly transformed into CNTs in highly confined spaces by high temperature Joule heating. Combined with experimental measurements and molecular dynamics simulations, we propose that Joule heating induces a high local temperature at defect sites due to the corresponding high local resistance. The resultant temperature gradient in amorphous carbon or RGO drives the migration of carbon atoms and promotes the growth of CNTs without using a catalyst or external carbon source. Our findings on the growth of CNTs in confined spaces by fast high temperature Joule heating shed light on the controlled transition between different carbon allotropes, which can be extended to the growth of other high aspect ratio nanomaterials.

IntroductionComplete and specific ablation of a single dopaminergic (DA) pathway is a critical step to distinguish the roles of DA pathways in vivo. However, this kind of technique has not been reported in non-human primates. This study aimed to establish a lesioning method with a complete and specific ablation.MethodA carefully designed infusion route based on a MRI stereotactic technique was developed to deliver the highly selective dopaminergic toxin 1-methyl-4-phenylpyridinium (MPP+) unilaterally into multiple sites of compact part of substantia nigra (SNc) and striatum in monkeys. The nigrostriatal DA pathway was selected because lesioning of this pathway may induce symptoms that are suitable for evaluation. The pathological, behavioral, neuropharmacological, and clinical laboratorial data were collected to evaluate the lesioning effects.ResultPathological examination revealed a complete ablation of tyrosine hydroxylase positive (TH+) neurons in the SNc, while preserving intact TH+ neurons in the ventral tegmental area (VTA) nearby. TH+ projections in the striatum were also unilaterally lost. The monkeys displayed stable (>28 weeks) rotations and symptoms which were expected with loss of DA neurons in the SNc, with rest tremor being an exception. No item implied the presence of a severe side effect caused by the operation or the intracerebral MPP+ infusion. The results suggested that rest tremor may not directly rely on the nigrostriatal pathway.ConclusionTaken together, in addition to providing a specific nigrostriatal DA lesioned model, this method, combined with brain stimulation or other techniques, can be applied as a powerful tool for the complete lesion of any desired DA pathway in order to study its specific functions in the brain.

(1 − x)(Bi1/2Na1/2)TiO3 − xBaTiO3 has been the most studied Pb-free piezoelectric material in the last decade; however, puzzles still remain about its phase transitions, especially around the important morphotropic phase boundary (MPB). By introducing the strain glass transition concept from the ferroelastic field, it was found that the phase transition from tetragonal (T, P4bm) to rhombohedral (R, R3c) was affected by a strain glass transition at higher temperature for x ≥ 4%. In these compositions, the T–R transition was delayed or even totally suppressed and displayed huge thermal hysteresis upon cooling and heating. Also, isothermal phase transitions were predicted and realized successfully in the crossover region, where the interaction between the T–R transition and the strain glass transition was strong. Our results revealed the strain glass nature in compositions around the MPB in this important material, and also provide new clues for understanding the transition complexity in other (Bi1/2Na1/2)TiO3-based Pb-free piezoelectric materials.

Traditionally, the determination of isotope ratios is analyzed by mass spectrometry (MS) method, which is usually destructive to sample (i.e., sample dissolution). Furthermore, the 58Fe abundance (0.282%) is generally rather low relative to other Fe isotopes, therefore, 58Fe/54Fe results is not reported in the routine measurement for MS methods. Given the importance of investigating a possible genetic relationship between the stable isotope composition of the Moon and the Earth, here, we firstly report the isotope ratios of 58Fe/54Fe in the Chang'E-5 (CE-5) scooped bulk lunar sample. In this work, the 58Fe/54Fe ratios were analyzed by instrumental neutron activation analysis (INAA) which is essentially distinguished and a potentially complementary advantage for MS in the determination of stable isotope ratios. These data obtained for the CE-5 lunar sample were also compared with those of terrestrial sample GBW07105. [ABSTRACT FROM AUTHOR]