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The mutual synergistic regulation of the multi-functional sites on a single receptor molecule for ion-binding/recognition is vital for the new receptor design and needs to be well explored from experiment and theory. In this work, a new macrocyclic ion receptor (BEBUR) with three functional zones, including two ether holes and one biurea groups, is designed expecting to mutually enhance the ion-binding performance. The binding behaviors of BEBUR mainly for Cl− and Cs+ are deeply investigated by using density functional theoretical calculations. It is found that Cl−/Cs+ binding can be mutually enhanced and synergistically regulated via corresponding conformational changes of the receptor, well reflecting an electrical complementary matching and mutual reinforcement effect. Moreover, solvent effect calculations indicate that BEBUR may be an excellent candidate structure for Cl−-binding with the enhancement of counter ion (Cs+) in water and toluene. In addition, visualization of intermolecular noncovalent interaction is used for analysis on the nature of the binding interactions between receptor and ions. [ABSTRACT FROM AUTHOR]

Tin-based perovskite solar cells are expected to replace lead-based perovskite solar cells to achieve environmentally friendly devices. Currently, a significant challenge lies in low filling factor and short-circuit current density, leading to an overall lower efficiency of these cells. In this context, we conducted a comprehensive comparative study on the deposition of these three inorganic small-molecule materials (CsBr, CsCl, CsI) on tin-based perovskite layers. The results showed that depositing these three inorganic small-molecule materials (CsBr, CsCl, CsI) on tin-based perovskite layers can improve the topography of the thin film and display an increased grain size. Simultaneously, the presence of the passivation layer facilitates preferred crystal orientation and enhanced charge carrier transport capabilities. Furthermore, devices with passivation layers exhibit reduced series resistance and increased shunt resistance, leading to a higher filling factor, a higher short-circuit current density, and a reduced leakage current in the passivated devices. This results in an elevated overall conversion efficiency of the devices. Notably, among the three halide materials employed for passivation, CsI demonstrates the most effective passivation, with the champion device achieving an efficiency of 6.0%. This study contributes valuable insights into the passivation strategies for tin-based perovskite solar cells. [ABSTRACT FROM AUTHOR]

Halide perovskite nanocrystals are at the forefront of materials research due to their remarkable optoelectronic properties and versatile applications. While their lattice structure and optical properties have been extensively investigated for the structure–property correlation, their lattice dynamics, the physical link between the lattice structure and optoelectronic properties, has been much less visited. We report the evolution of structural dynamics of a series of cesium lead halide perovskite nanocrystals whose size and morphology are systematically varied by synthesis temperature. Low-frequency Raman spectroscopy uncovers the nanocrystals' structural dynamics, including a relaxational spectral continuum from ligand librations and a phonon spectrum evolving with nanocrystal size. As the size of nanocrystals increases, their phonon spectrum becomes more intense, and their spectral weights redistribute with new first- and second-order modes being activated. The linewidth of the observed phonon modes generally broadens as the nanocrystal grows larger, an interesting deviation from the established phonon confinement model. We suggest that strong confinement and truncation of the lattice and ligands anchoring on the surface might lead to pinning of the lattice dynamics at nanoscale. These findings offer new insights into the bulk–nano-transition in halide perovskite soft semiconductors. [ABSTRACT FROM AUTHOR]

Over the past decade, the certified power conversion efficiency of perovskite solar cells (PSCs) has increased to 26.1%. However, phase instability originating from lattice strains, has limited their commercialization. Strains will inevitably be generated during the PSC fabrication and service process due to the "soft lattice" nature of halide perovskites. In particular, flexible PSCs are subjected to not only mechanical tensile and compressive loads, but also suffer from thermal stresses. In this study, strain-induced changes in the phase stability and the corresponding optoelectronic properties of CsPbI3−xBrx (CsPbI3, CsPbBr3, and CsPbI2Br) systems under tensile and compressive stresses were investigated using first-principles calculations. The results showed that compressive stresses reduce the bandgap value and increase the light absorption coefficient; thus, the optoelectronic performance is improved, whereas the light absorption coefficient decreases regardless of how the bandgap changes under tensile stresses. Moreover, under the same stress, the tensile strain value was twice that of the compressive strain, and the critical value of the transition from the cubic to tetragonal phase was lower, indicating that phase stability was worse under tensile stresses. Therefore, during the fabrication of PSCs, the tensile stress state should be adjusted to the compressive stress state, which is favorable for enhancing PSCs photovoltaic performance and phase stability. The results not only provide direct evidence of tensile and compressive strains influencing the phase stability and optoelectronic property changes in halide perovskites, but also highlight lattice-strain tailoring for the composition design, process optimization, and interface engineering of efficient and stable PSCs. [ABSTRACT FROM AUTHOR]

We report the experimental measurements of the decay rate of polar cesium nD5/2 − 6S1/2 Rydberg-ground molecules with a large principal quantum number range of 35 ≤ n ≤ 40. Rydberg molecules are prepared employing the method of two-photon photoassociation and the molecular (atomic) ions, due to autoionization (blackbody photoionization), are detected with a microchannel plate detector. The decay rate Γ of the vibrational ground state of the deep and shadow bound molecules for triplet (TΣ) and mixed singlet-triplet (S,TΣ) are measured by fitting the molecular population with the exponential function. Comparing with the parent atom, the decay rate of the polar Rydberg-ground molecule shows an obvious increase with a magnitude of a few μs. The possible dissociation mechanism of polar Rydberg-ground molecules including a collisional decay, blackbody induced decay, and coupling of adjacent Rydberg states and tunneling decay are discussed in detail. The theoretical model is induced to simulate the measurements, showing agreement. [ABSTRACT FROM AUTHOR]

Anion exchange is a facile, post-synthetic method to tune the emission wavelength of colloidal cesium lead halide (CsPbX3, X = Cl, Br, I) perovskite nanocrystals. While colloidal nanocrystals can exhibit size-dependent phase stability and chemical reactivity, the role of size in the mechanism of anion exchange in CsPbX3 nanocrystals has not been elucidated. We used single-particle fluorescence microscopy to monitor the transformation of individual CsPbBr3 nanocrystals to CsPbI3. By systematically varying the size of the nanocrystals and the concentration of substitutional iodide, we observed that smaller nanocrystals exhibit longer transition times in their fluorescence trajectories, while larger nanocrystals undergo a more abrupt transition during anion exchange. Monte Carlo simulations were used to rationalize the size-dependent reactivity, in which we varied how each exchange event affects the probability for further exchange. Greater cooperativity for simulated ion exchange leads to shorter transition times to complete the exchange. We propose that size-dependent miscibility between CsPbBr3 and CsPbI3 at the nanoscale controls the reaction kinetics. Smaller nanocrystals maintain a homogeneous composition during anion exchange. As the nanocrystal size increases, variations in the octahedral tilting patterns of the perovskite crystals lead to different structures for CsPbBr3 and CsPbI3. Thus, an iodide-rich region must first nucleate within larger CsPbBr3 nanocrystals, which is followed by rapid transformation to CsPbI3. While higher concentrations of substitutional anions can suppress this size-dependent reactivity, the inherent differences in reactivity between nanocrystals of different sizes are important to consider when scaling up this reaction for applications in solid-state lighting and biological imaging. [ABSTRACT FROM AUTHOR]

High-performance and low-cost metal halide perovskite scintillator materials have important applications in X-ray detection and imaging. However, large-sized perovskite scintillator panel with high transmittance, low toxicity and long-term stability is still lacking. Herein, Eu2+ doped cesium alkaline earth chloride nanocrystals (Eu2+: CsCaCl 3 , Eu2+: CsSrCl 3 , and Eu2+: Cs 2 BaCl 4 NCs) embedded in glasses through conventional melt-quenching and subsequent heat-treatment were developed. These NCs doped glasses exhibited highly efficient and narrowband photoluminescence in blue region. Benefitting from the large X-ray absorption coefficient and high photoluminescence quantum yied, these Eu2+: CsCaCl 3 NCs doped glass scintillator shows light yield of ∼9300 photons/MeV, detection limit of ∼213.8 μGy/s, and spatial resolution of 30.0 lp/mm. These results demonstrated that glasses containing Eu2+ doped cesium alkaline earth chloride nanocrystals are promising for X-ray detection and imaging. [ABSTRACT FROM AUTHOR]

Incomplete resection rates vary among endoscopists performing cold snare polypectomy. Cold snare endoscopic mucosal resection (CS-EMR) is the technique of cold resection after submucosal injection to reduce incomplete resection. This study aimed to evaluate the efficacy and safety of CS-EMR for small colorectal polyps compared to hot snare endoscopic mucosal resection (HS-EMR). Preplanned sample size required 70 polyps to CS-EMR group or HS-EMR group, respectively. Patients with polyps sized 6–9 mm were randomly allocated to either the CS-EMR or the HS-EMR group. The primary outcome was residual or recurrent adenoma (RAA) rate. A total of 70 and 68 polyps were resected using CS-EMR and HS-EMR, respectively. In the intention-to-treat population, the RAA rate was 0% in the CS-EMR group and 1.5% in the HS-EMR group (risk difference [RD], − 1.47; 95% confidence interval [CI] − 4.34 to 1.39). En bloc resection rate was 98.6% and 98.5% (RD, − 0.04; 95% CI − 4.12 to 4.02); the R0 resection rate was 55.7% and 82.4% (RD, − 27.80; 95% CI − 42.50 to − 13.10). The total procedure time was 172 s (IQR, 158–189) in the CS-EMR group and 186 s (IQR, 147–216) in the HS-EMR group (median difference, − 14; 95% CI − 32 to 2). Delayed bleeding was 2.9% vs 1.5% (RD, 1.37; 95% CI − 3.47 to 6.21) in both groups, respectively. CS-EMR was non-inferior to HS-EMR for the treatment of small colorectal polyps. CS-EMR can be considered one of the standard methods for the removal of colorectal polyps sized 6–9 mm. [ABSTRACT FROM AUTHOR]

Abstract\nNOVELTY STATEMENTThe combined microbial-plant remediation has increasingly been used to remediate heavy metal-contaminated soil. Some microorganisms could enhance phytoremediation efficiency by solubilizing heavy metal and improve plant growth by producing phytohormones in the heavy metal contaminated soils. In the present study, a strong cesium (Cs)-tolerant fungal strain Paecilomyces lilacinus was identified from soil microorganisms contaminated with Cs, and the enrichment conditions for Cs were optimized. Furthermore, the effects of the A10 fermentation solution on the growth of Indian mustard (Brassica juncea L.) seedlings were investigated. The results indicated that the optimal combination of factors consisted of a culture temperature of 28 °C, pH7.0, initial concentration of Cs at 5.91 g·L−1. The maximum enrichment of Cs in the A10 was up to 75.36 mg·g−1 DW. In addition, the enrichment of Cs in Indian mustard was significantly enhanced by the application of the A10 fermentation solution, and the growth of Indian mustard was promoted under Cs stress. The present study has expanded the repertoire of microbial resources available for facilitating the Cs contaminated soil, thereby enhancing its applicability in the phytoremediation strategies.Recently, cesium (Cs) pollution has become a global environmental problem. Although much attention has been paid to combined microbe-plant remediation, there is still a lack of microbial strains with efficient Cs adsorption capacity to assist phytoremediation. The present study identified a new Cs accumulation fungus that effectively enhances the growth of Brassica juncea L. under Cs stress. In a word, the findings of this study have expanded the repertoire of microbial resources available for facilitating the Cs contaminated soil, thereby enhancing its applicability in the phytoremediation strategies. [ABSTRACT FROM AUTHOR]

Efficient and stable scintillators play a crucial role in X‐ray detection applications. To enhance the luminescence efficiency under X‐ray excitation, the incorporation of multiple emission centers into scintillators is widely explored. Here, it is found that the cesium copper halide Cs5Cu3Cl6I2 exhibits dual emission centers, enabling high‐performance scintillators with an X‐ray light yield of 49000 photon MeV−1 and a low detection limit of 4 nGy s−1. The emissions of Cs5Cu3Cl6I2 are from intrinsic self‐trapped exciton (STE) and Frenkel defect‐assisted STE. High‐energy X‐rays can induce an increased fraction of Frenkel defect‐assisted STEs, which can serve as an effective scintillation channel. Furthermore, large‐area flexible scintillators with a high resolution of 18 lp mm−1 are developed, making them suitable for X‐ray imaging applications. These findings offer promising insights for developing more efficient scintillators. [ABSTRACT FROM AUTHOR]

• The adsorption capacity of ZnFC-PA/PSF composite spheres for Cs+ was 305.38 mg/g. • Its practicability is superior than of most previously reported adsorbents. • A fixed bed reactor loaded with ZnFC-PA/PSF spheres was used for cesium removal. • The effects of operating parameters on the breakthrough curves were investigated. Radioisotope leaking from nuclear waste has become an intractable problem due to its gamma radiation and strong water solubility. In this work, a novel porous ZnFC-PA/PSF composite sphere was fabricated by immobilization of ferrocyanides modified zinc phytate into polysulfone (PSF) substrate for the treatment of Cs-contaminated water. The maximum adsorption capacity of ZnFC-PA/PSF was 305.38 mg/g, and the removal efficiency of Cs+ was reached 94.27% within 2 hr. The ZnFC-PA/PSF presented favorable stability with negligible dissolution loss of Zn2+ and Fe2+ (< 2%). The ZnFC-PA/PSF achieved high-selectivity towards Cs+ (K d = 2.24×104 mL/g) even in actual geothermal water. The adsorption mechanism was inferred to be the ion-exchange between Cs+ and K+. What's more, ZnFC-PA/PSF worked well in the fixed-bed adsorption (E = 91.92%), indicating the application potential for the hazardous Cs+ removal from wastewater. [Display omitted] [ABSTRACT FROM AUTHOR]

The trifluoromethyl group (CF3) is a key functionality in pharmaceutical and agrochemical development, greatly enhancing the efficacy and properties of resulting compounds. However, attaching the CF3 group to heteroatoms such as sulfur, oxygen, and nitrogen poses challenges because of the lack of general synthetic methods and reliance on bespoke reagents. Here, we present a modular flow platform that streamlines the synthesis of heteroatom-CF3 motifs. Our method uses readily available organic precursors in combination with cesium fluoride as the primary fluorine source, facilitating the rapid generation of N-trifluoromethyl(R) [NCF3(R)], SCF3 (trifluoromethylthio), and OCF3 (trifluoromethoxy) anions on demand without reliance on perfluoroalkyl precursor reagents. This strategy offers a more environmentally friendly synthesis of trifluoromethyl(heteroatom)-containing molecules, with the potential for scalability in manufacturing processes facilitated by flow technology. [ABSTRACT FROM AUTHOR]

In the modern era, the major problem is solving energy production and consumption. For this purpose, perovskite materials meet these issues and fulfill energy production at a low cost. Density functional theory and the Cambridge Serial Total Energy Package (CASTEP) are used to examine the characteristics of the cubic inorganic perovskites RPbBr3 (R = Cs, Hg, and Ga). In the context of the generalized gradient approximation (GGA), the ultrasoft pseudo-potential plane wave technique and the Perdew–Burke–Ernzerhof exchange–correlation functional are used for investigations. Structural, mechanical, electronics, and optical properties are investigated using CASTEP code. According to structural properties, compounds have a cubic nature with space 221 (Pm3m). Compounds formation energy (− 3.46, − 2.21, and − 3.14 eV)of (CsPbBr3, HgPbBr3, and GaPbBr3) and phonon calculations are studied and find that compounds are stable. The results of our investigation show that the compounds have narrow bandgaps of direct kind, with 1.85 eV for CsPbBr3, 1.56 eV for HgPbBr3, and 1.71 eV for GaPbBr3, respectively, indicating that they may be used to improve conductivity. Additionally, anisotropy (2.135, 3.651, 10.602), Pugh's ratio (1.87, 2.25, 2.14), and Poison's ratio (0.27, 0.31, 0.29) are traits that the compounds (CsPbBr3, HgPbBr3, GaPbBr3) display a ductile nature. The CsPbBr3 compound showed significant optical conductivity and absorption in terms of their optical properties, especially in the visible region, which makes them suitable for use in solar cell applications as well as for LED applications. [ABSTRACT FROM AUTHOR]

Lead-free halide perovskites have attracted widespread research interest due to their excellent optoelectronic properties and environmental friendliness. As one of the bismuth iodide compounds, Cs3Bi2I9 perovskite has been extensively explored in the field of photovoltaic devices and radiation detectors due to their non-toxic lead-free components and excellent stability. In this work, we successfully grow large-sized Cs3Bi2I9 single crystals (SC) with (l 00) and (00 l) crystal exposure facets by inverse temperature crystallization method. Under 525 nm light illumination with the intensity 15 mW cm−2 and 7 V bias, the (l 00) Cs3Bi2I9 SC shows 2 times higher photocurrent, 3.6 times higher responsivity, and 2.8 times higher detectivity than the (00 l) Cs3Bi2I9 SC, respectively. Superior response time in the scale of millisecond is obtained in both (l 00) and (00 l) Cs3Bi2I9 SCs. Based on the first-principle calculation, the (l 00) SC possesses a higher charge distribution density and a wider dispersion distribution than (00 l) SC, suggesting that more electrons in the (l 00) SC can be excited in a wider range. The tighter arrangement of Cs+ and [BiI6]− octahedra in the (l 00) SC than (00 l) SC leads to the anisotropic photoelectric performance in (l 00) and (00 l) Cs3Bi2I9 SCs. Our results provide a strategy for the oriental growth of Cs3Bi2I9 SCs and the design of anisotropic optoelectronic devices with excellent performance. [ABSTRACT FROM AUTHOR]

Cesium-137 (Cs-(I)) is highly hazardous in low-level wastewater and is a major problem in low-level nuclear wastewater. Its effective removal from contaminated wastewater is crucial to ensuring environmental safety and public health. In this study, cesium ion-imprinted composite membranes (I-DBC) were developed for selective separation of Cs-(I) using dopamine modification and ion-imprinting techniques. Bacterial cellulose (BC) was used as a carrier in the membrane matrix, and the adsorption capacity of the material was greatly improved after hydrophilic dopamine mimetic bonding and ion blotting techniques. Rapid and highly selective adsorption of cesium ions from low concentration nuclear energy wastewater was realized. The researchers conducted both static and dynamic adsorption experiments on Cs-(I) to evaluate the performance of the I-DBC composite membranes. The results showed that the I-DBC composite membrane was more compatible with the Langmuir model and adsorbed Cs-(I) mainly by chemical monolayer adsorption, with a maximum adsorption capacity of 50.016 mg g–1 under optimal conditions. In low concentration wastewater, the maximum adsorption capacity of the I-DBC was 4.093 mg g–1. Furthermore, during dynamic permeation experiments, the breakthrough point of the I-DBC was approximately 20 min. The membrane demonstrated good flux properties, which underscores its potential for practical application in the treatment of nuclear wastewater. The findings suggest that the I-DBC composite membrane holds promising prospects for the efficient removal of cesium ions from contaminated water, contributing to safer and more effective nuclear wastewater management. [ABSTRACT FROM AUTHOR]

Recently, lanthanide‐based 0D metal halides have garnered considerable attention owing to their applications in light–emitting diodes (LEDs), X‐ray imaging, and photodetectors. Among these materials, 0D Cs3TbCl6 (CTC) nanocrystals (NCs) have demonstrated promising performance in X‐ray imaging and light‐emitting diodes. However, a considerable drawback of CTC NCs is their limited absorption coefficient in the UV‐A region (315–380 nm). To address this limitation and enhance the absorption coefficient in the UV‐A region, Ce3+ is incorporated into CTC NCs—advantageous owing to the high absorption coefficient of Ce3+ in the UV‐A region, attributed to—4f‐5d orbital coupling. In addition, Ce3+ ions sensitize the luminescence of CTC NCs and enhance the photoluminescence quantum yield from 75% to 87%. Energy transfer from Ce3+ to Tb3+ is investigated at different dopant ratios. Furthermore, Cs3CeTbCl6 (CCTC) NCs have been utilized in white LED devices. Understanding such competitive energy transfer in lanthanide‐based perovskite‐inspired metal halides will facilitate the development of novel luminescent metal halides for lighting applications. [ABSTRACT FROM AUTHOR]

This study prepares a series of hollow‐structured CS/SA/POSS composite gel spheres with a diameter of ~2.5 mm by using hydrophilic Janus‐type polyhedral oligomeric silsesquioxane (AS‐POSS) as a crosslinking agent in combination with sodium alginate and chitosan via electrostatic adsorption/free radical polymerization. As the content of POSS increases, the wall thickness of the gel spheres also increases from 20 to 30 μm, leading to a more compact and smooth wall structure in the polymerized CS/SA/POSS composite gel spheres. Additionally, the introduction and polymerization of POSS significantly enhance the stability, drug loading rate, and entrapment rate of the gel spheres, providing them with improved drug release capabilities. For hydrophilic drug doxorubicin, the loading rate and encapsulation rate reach 41.2% and 79.9%, respectively, while for the hydrophobic drug ibuprofen, they are 14.7% and 76.3%. Compared to some previously reported drug‐loaded gel materials, the gels prepared in this study demonstrate relatively higher drug loading performance. Thus, these hollow‐structured CS/SA/POSS composite gel spheres hold promise as innovative drug carriers in the biomedical field. [ABSTRACT FROM AUTHOR]

We report an idea for the synthesis of oligopeptides using a solvent‐free ball milling approach. Our concept is inspired by block play, in which it is possible to construct different objects using segments (blocks) of different sizes and lengths. We prove that by having a library of short peptides and employing the ball mill mechanosynthesis (BMMS) method, peptides can be easily coupled to form different oligopeptides with the desired functional and biological properties. Optimizing the BMMS process we found that the best yields we obtained when TBTU and cesium carbonate were used as reagents. The role of Cs2CO3 in the coupling mechanism was followed on each stage of synthesis by 1H, 13C and 133Cs NMR employing Magic Angle Spinning (MAS) techniques. It was found that cesium carbonate acts not only as a base but is also responsible for the activation of substrates and intermediates. The unique information about the BMMS mechanism is based on the analysis of 2D NMR data. The power of BMMS is proved by the example of different peptide combinations, 2+2, 3+2, 4+2, 5+2 and 4+4. The tetra‐, penta‐, hexa‐, hepta‐ and octapeptides obtained under this project were fully characterized by MS and NMR techniques. [ABSTRACT FROM AUTHOR]

The article describes for the first time the synthesis of the diaminoacetylene ligand, which is a by-product of the synthesis of [W(CN)6(bpy)]2− involving the thermal decomposition of (bpyH)3(H3O)[W(CN)8]·H2O. The formation of the diaminoacetylene ligand, H2NC≡CNH2, occurs through protonation of cyanido ligands and the formation of a C–C bond between two neighbouring CN− ligands through a reductive coupling mechanism. In this way, three salts of the anion [W(CN)6(C2N2H4)]2− with cations: PPh4+ (1), rubidium (2), and caesium (3) were isolated and then structurally and spectroscopically characterised. The formation of an additional by-product (PPh4)3[W(CN)8]·4.25H2O (4) was also discussed. IR measurements of the reaction mixture indicate that proton transfer from the Hbpy+ cation is accompanied by the formation of the acetylene ligand. NMR spectra indicate strong interactions between the cyanido ligands and the protons of the acetylene ligand. [ABSTRACT FROM AUTHOR]

Crown ether‐assisted supramolecular assembly is a robust strategy for manipulating low‐dimensional metal halides. In this study, the supramolecular assembly of 0D‐Cs3Cu2I5 is presented. Upon the addition of 15‐crown‐5 (15C5) to Cs3Cu2I5, 15C5 immediately coordinates with Cs+ to form the cone‐shaped [(15C5)Cs]+. Simultaneously, one of the iodine atoms is removed from the [Cu2I5]3‐ cluster, resulting in the formation of a sub‐planar rhombic [Cu2I4]2− unit. This process leads to white emission, specifically [(15C5)Cs]2[Cu2I4], which exhibits a photoluminescence quantum yield (PLQY) close to unity. The [(15C5)Cs]+ further reacts with 15C5 to form the sandwich‐type cationic structure [(15C5)2Cs]+, accompanied by the generation of red emission [(15C5)2Cs]2[Cu2I4]. By carefully controlling the amount of 15C5, various emission composites can be achieved, particularly tunable white emission. The assembly process is reversible. The pristine Cs3Cu2I5 can be recovered after thermal curing because of the volatility of crown ether and the weak Cs‐crown ether bond. Theoretical calculations have demonstrated that the coordination of the crown ether primarily affects the energy level, leading to changes in the excited state and photophysical properties. The applications in anticounterfeiting and LED phosphors have been demonstrated. This work provides a new approach for the development of low‐dimensional copper halides with promising applications in optoelectronics. [ABSTRACT FROM AUTHOR]

While organoelement compounds of lithium, sodium and potassium have been much studied for decades and consequently have found forests of applications, those of the heavier alkali metals, rubidium and caesium would barely manage to fill a tree. However, recently the literature has seen some little growth spurts with these metals, hinting at a possible fertile future in areas such as homogeneous catalysis provided more work is put into their fundamental development. Here we report the synthesis and crystal structures of lithium, rubidium and caesium derivatives of the ureaphosphane Ph2PCH2CH2NHC(=O)NHPh, chosen because it offers O, N, P, and π‐coordination sites. Though one may expect such alkali metal compounds to be essentially similar, the caesium complex has novel features where Cs+ engages in a side‐on coordination to the C=O bond and in a weak bond to the P centre, both of which are absent in the Rb structure. Less surprisingly, the lithium derivative is tetrameric in contrast to the infinite networks of the rubidium and caesium structures. All alkali metal derivatives were made with deprotonating the ureaphosphane by a suitable base, including the sodium and potassium complexes though these two complexes could not be obtained in a crystalline form. [ABSTRACT FROM AUTHOR]

A hydrothermal method which can convert free cesium ions into stable pollucite at low temperatures was established in this work, avoiding any evaporation pollution during the disposal of cesium containing waste. Meanwhile, rapid synthesis under hydrothermal conditions was achieved using seed guidance, which shorten the growth time of pollucite crystals to 8 h, and making the treatment and disposal of cesium containing wastewater faster. Standard leaching test results show that the leaching rate of Cs was very low (< 3.5 × 10−7 g·m2·d), it still has good thermal stability at a temperature of 1300 °C, when the cesium content in pollucite reaches 20%. [ABSTRACT FROM AUTHOR]

Radioactive nuclides cesium (Cs) and strontium (Sr) possess long half-lives, with 135Cs at approximately 2.3 million years and 87Sr at about 49 billion years. Their persistent accumulation can result in long-lasting radioactive contamination of soil ecosystems. This study employed geo-accumulation index (Igeo), pollution load index (PLI), potential ecological risk index (PEPI), health risk assessment model (HRA), and Monte Carlo simulation to evaluate the pollution and health risks of Cs and Sr in the surface soil of different functional areas in a typical mining city in China. Positive matrix factorization (PMF) model was used to elucidate the potential sources of Cs and Sr and the respective contribution rates of natural and anthropogenic sources. The findings indicate that soils in the mining area exhibited significantly higher levels of Cs and Sr pollution compared to smelting factory area, agricultural area, and urban residential area. Strontium did not pose a potential ecological risk in any studied functional area. The non-carcinogenic health risk of Sr to the human body in the study area was relatively low. Because of the lack of parameters for Cs, the potential ecological and human health risks of Cs was not calculated. The primary source of Cs in the soil was identified as the parent material from which the soil developed, while Sr mainly originated from associated contamination caused by mining activities. This research provides data for the control of Cs and Sr pollution in the surface soil of mining city. [ABSTRACT FROM AUTHOR]

High-precision magnetometers play a crucial role in ocean exploration, geophysical prospecting, and military and security applications. Installing them on human-occupied vehicle (HOV) platforms can greatly enhance ocean exploration capabilities and efficiency. However, most existing magnetometers suffer from low sensitivity and excessively large size. This study presents a high-sensitivity, miniaturized magnetometer based on cesium optically pumped probes. The designed magnetometer utilizes a three-probe design to eliminate the detection dead zone of the cesium optically pumped probe and enable three-dimensional magnetic detection. The proposed magnetometer uses a flux gate probe to detect the three-axis magnetic field and ensure that the probe does not enter the dead zone. The three probes can automatically switch by measuring the geomagnetic elements and real-time attitude of the HOV platform. This article primarily introduces the cesium three-probe optically pump, flux gate sensor, and automatic switching scheme design of the above-mentioned magnetometer. Moreover, it is proven through testing that the core indicators, such as the accuracy and sensitivity of the cesium three-probe optically pumped and flux gate sensor, reach international standards. Finally, the effectiveness of the automatic switching scheme proposed in this study is demonstrated through drone-mounted experiments. [ABSTRACT FROM AUTHOR]

The instability of perovskite solar cells (PSCs) remains a major bottleneck for their commercialization, with thermal instability posing a major concern, given the inevitable presence of heat in photovoltaic devices. Mixed‐cation/halide perovskites demonstrate enhanced stability and efficiency compared to single‐cation/halide perovskites. Identifying the optimal perovskite composition capable of withstanding high temperatures for longer durations is crucial for the development of thermally stable PSCs. This study provides valuable insights into the optimization of mixed‐cation/halide perovskites to enhance the thermal and structural stability of perovskite films. By systematically varying the Cs content in FA1−yCsyPb(I0.85Br0.15)3 (0 < y < 25)‐based perovskite, it is observed that controlling the Cs content allows precise modulation of crystal orientation in perovskite film with 10% Cs obtained as the optimal value. The perovskite film containing 10% Cs not only exhibits reduced microstrain but also demonstrates enhanced thermal stability during testing at 85 °C under controlled humidity. Furthermore, planar PSCs are fabricated using FA0.90Cs0.10Pb(I0.85Br0.15)3 as the absorber layer and TOP‐3 as the hole‐transporting material, achieving a promising power conversion efficiency (PCE) of 17.70%. Impressively, the unencapsulated devices retain 95% of their initial PCE after 1000 h of dark storage under ambient conditions. [ABSTRACT FROM AUTHOR]

Solar‐powered interfacial evaporation is recognized as an emerging technology for desalination of salt‐lake water but suffers from insufficient evaporation mass under intermittent sunlight illumination. Meanwhile, salt‐lake water contains abundant noble metal ions; however, there is no effective strategy to extract them during evaporation. Hereby, an interfacial evaporator integrated with crown‐ether‐functionalized phase‐change microcapsules (Crown‐MicPCM) is designed to realize all‐weather desalination and synchronous caesium ion (Cs+) extraction of salt‐lake water. Crown‐MicPCM is constructed with an n‐docosane core for photothermal energy storage, a magnetic SiO2/Fe3O4 composite shell for easy recyclability, a polydopamine inner coat for sunlight absorption, and a crown ether outer coat for selective Cs+ adsorption. Through integrating the functions of solar energy harvest, latent heat storage, and selective Cs+ adsorption within Crown‐MicPCM, such an innovative design boosts the evaporation and adsorption performance of the developed evaporator significantly. The developed Crown‐MicPCM‐integrated evaporator exhibits a considerable improvement in freshwater production and Cs+ extraction, achieving a Cs+ adsorption capacity of 32.6 mg g−1 and an evaporation rate of 1.43 kg m−2 h−1 under one‐sun illumination. Compared with the evaporator without a phase‐change material, the Crown‐MicPCM‐integrated evaporator obtains an increase in freshwater yield by 47% and in adsorption efficiency of Cs+ by 12% under natural sunlight illumination. [ABSTRACT FROM AUTHOR]

Rare earth ions with d-f transitions (Ce3+, Eu2+) have emerged as promising candidates for electroluminescence applications due to their abundant emission spectra, high light conversion efficiency, and excellent stability. However, directly injecting charge into 4f orbitals remains a significant challenge, resulting in unsatisfied external quantum efficiency and high operating voltage in rare earth light-emitting diodes. Herein, we propose a scheme to solve the difficulty by utilizing the energy transfer process. X-ray photoelectron spectroscopy and transient absorption spectra suggest that the Cs3CeI6 luminescence process is primarily driven by the energy transfer from the I2-based self-trapped exciton to the Ce-based Frenkel exciton. Furthermore, energy transfer efficiency is largely improved by enhancing the spectra overlap between the self-trapped exciton emission and the Ce-based Frenkel exciton excitation. When implemented as an active layer in light-emitting diodes, they show the maximum brightness and external quantum efficiency of 1073 cd m−2 and 7.9%, respectively. Rare-earth metal halide perovskites are promising for deep blue LEDs. Here, Yang et al. report energy transfer between self-trapped exciton and Frenkel exciton in Cs3CeI6 by adding excess CsI during thermal evaporation, resulting in deep blue LEDs with external quantum efficiency of 7.9% at 424 nm. [ABSTRACT FROM AUTHOR]

As the utilization of nuclear energy continues to expand, there is a growing focus on the development of lightweight and efficient nuclear shielding composites. In this paper, novel WB X /Al (x = 1, 2, 4) composites were designed based on shielding performance. The effects of reinforcement type, volume fraction, and material thickness on the 60Co and 137Cs γ-rays, fast and thermal neutron shielding performances were simulated. The results show that WB/Al composites offer better development potential compared to WB 2 /Al or WB 4 /Al composites. Additionally, a predictive model for the γ-ray shielding effectiveness of WB/Al composites, based on the areal density of tungsten, was proposed. The fabrication process involved mechanical ball milling and spark plasma sintering to fabricate 30 vol% WB/Al composites, with optimization of ball milling time, sintering temperature, and holding time. As a result, a novel nuclear radiation protection composite with uniform composition, a relative density of 97 %, and flexural strength of 527 MPa was acquired. [ABSTRACT FROM AUTHOR]

Organic light‐emitting diodes have a huge gain in popularity over the past 25 years for display and lighting applications, but the production of low‐cost efficient devices remains a challenge. OLEDs using sub‐nanometer undoped emissive layers are a route to fabricate cost‐effective devices but, as they are inherently thin, it opens to issues with variation in thickness and shunting paths. At the same time, lead chloride perovskites are currently being investigated as charge transport materials in light‐emitting devices owing to their wide bandgap, and remarkable high carrier mobility. In this work, for the first time, OLEDs that combine vacuum‐processed thick cesium lead chloride perovskite hole transport layers with ultrathin Ir complex‐based emissive layers are reported. Defects on the perovskite film are suppressed and the thickness of the emitting layer is optimized. Semitransparent devices are also fabricated with an average visible transmittance of over 50%. The results show extraordinarily thick devices (>1 µm) with low turn‐on voltage (3.3 V), high luminance (>15 000 cd m−2) and efficiencies (up to 54.1 cd A−1), and a negligible efficiency roll‐off in the display applications luminance region. [ABSTRACT FROM AUTHOR]

While 20 % of radionuclides released from the Fukushima Daiichi Nuclear Power Plant accident had been deposited in the terrestrial environment, rivers remain the long-term source for 137Cs, primarily through particulate transfer, from terrestrial to marine ecosystems. In this study, we estimated the suspended 137Cs flux to the ocean at 11 sites in the coastal area between October 2012 and December 2020 to be 17 TBq, based on our long-term monitoring data of concentrations of suspended 137Cs and suspended solids. The cumulative loss of suspended 137Cs from each site to the ocean ranged from 0.1 % to 1.7 % of initial deposition throughout the observation period, depending on the effect of dam lakes and normalized river discharge. The higher loss is also thought to be the large outflow of runoff during the typhoon. The current level of the suspended 137Cs concentrations was lowered to 1/10–1/100 of those immediately after the accident. The average value of the decreasing trend for each site was approximated using the equation: y = a1 e −k1t + a2 e −k2t. The rate constant k1 is higher in areas with intensive land use, such as pastures, bare land, and water surfaces, and k2 is lower in urban areas. [ABSTRACT FROM AUTHOR]

In this work, vanadium-substituted cesium phosphomolybdate salts were evaluated as catalysts in glycerol furfural condensation reactions, an attractive route to produce fuel-green bioadditives. Molybdenum atoms of phosphomolybdic acid were substituted with vanadium and precipitated as cesium salts generating catalysts with general formulae Cs3+nPMo12-nVnO40 (n = 1–3). Among the salts evaluated, Cs4PMo11V1O40 was the most active and selective catalyst toward the glyceryl furfural acetals, isomers (dioxolane: dioxane) were obtained at 2: 1 molar ratio with 90% conversion after a 2 h reaction at room temperature. The effect of main reaction parameters such as the glycerol: furfural molar ratio, the catalyst load, solvent, vanadium load, and the temperature were studied. The use of a solid, active, and easily synthesizable catalyst makes this an attractive route to produce fuel bioadditives from renewable raw materials at room temperature. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) have emerged as promising candidates in PV research due to their exceptional photovoltaic properties. However, the toxicity and environmental concerns associated with lead‐based perovskites have led to the exploration of lead‐free alternatives. In this study, the performance of lead‐free bismuth PSCs, specifically PSCs based on Cesium Bismuth Iodide (Cs3Bi2I9) and Methyl Ammonium Bismuth Iodide (MA3Bi2I9), is investigated. Numerical simulations using the solar cell capacitance simulator (SCAPS) are conducted to comprehensively analyze the influence of key parameters, including the band‐to‐band radiative recombination rate, the absorber layer defect density, the absorber layer/electron transport layer (ETL) interface defect density, the absorber layer/hole transport layer interface (HTL) defect density, operating temperatures, and series and shunt resistances, and to optimize the proposed PSCs accordingly. The simulation results demonstrate a significant impact of these key parameters on the performance of Cs3Bi2I9 and MA3Bi2I9 PSCs. The optimized Cs3Bi2I9‐based PSC exhibited notable performance characteristics, including a PCE of 13.81%, a Voc of 1.16 V, a Jsc of 18.14 mA cm−2, and FF of 65.51%. In contrast, the MA3Bi2I9‐based PSC demonstrated relatively lower performance, with a PCE of 11.82%, Voc of 1.14 V, Jsc of 18.06 mA cm−2, and FF of 57.33%. The study on the defect density at the interfaces revealed the performance of PSCs is predominantly influenced by defects at the front interface (ETL/Absorber) rather than the rear interface (HTL/Absorber). These results provide valuable insights for the experimental design and optimization of lead‐free bismuth PSCs. [ABSTRACT FROM AUTHOR]

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There exist some perovskites materials with no photoluminescence (PL), which will greatly limit the practical applications in photodetection, display and lighting. Here, we achieve an exotic pressure-induced emission (PIE) at a mild pressure of 0.8 GPa from initially non-emissive 2D all-inorganic perovskite Cs3Sb2Br9 quantum dots, when the sample was subjected to external pressure. With the increase of pressure, the PL intensity gradually increases and the emission color transforms from red to green. Combined with subsequent experiments and computations, thus PIE behavior and piezochromism result from the SbBr6 octahedral distortion, accompanied by a structural phase transition from trigonal to monoclinic under pressure. Our work provides a robust strategy to boost the emission efficiency and to construct multi-functional PIE materials with piezochromism in environmentally friendly perovskites, thus facilitating the diverse applications in futural practices. [ABSTRACT FROM AUTHOR]

Ion migration adversely affects perovskite solar cell (PSC) performance by upsetting film stability, inducing hysteresis, and light-induced halide segregation. Ion migration is also substantially influenced by residual strains, which are prevalent in fabricated PSCs. This study thus utilizes molecular dynamics simulations to analyze the influence of uniaxial, biaxial, and isotropic states of compressive and tensile stresses on ion migration in single-crystal cesium lead iodide (CsPbI3) and bromide (CsPbBr3) perovskites. Furthermore, nudged elastic band simulations are used to reveal energy barriers associated with ion migration under mechanical deformation. Tensile and compressive strains are observed to intensify and inhibit ion migration, respectively, in these metal halide perovskites (MHPs), with the extent of this alteration becoming more drastic on progressing from uniaxial to isotropic state of stress. We also reveal that uniaxial and biaxial states of stresses induce anisotropic ion migration in CsPbI3, while ion migration remains isotropic under these loading conditions in CsPbBr3. The heightened ion migration under tension in these MHPs is deciphered to arise from lowering of the energy barrier, while migration inhibition under compression arises from increase in barrier height. This study thus provides direct evidence of tensile and compressive strains influencing ion migration in MHPs and highlights that methods such as lattice-strain tailoring that are aimed at mitigating this phenomenon may need to be customized to the MHP of interest. [ABSTRACT FROM AUTHOR]

The development of passive NOx adsorbers with cost-benefit and high NOx storage capacity remains an on-going challenge to after-treatment technologies at lower temperatures associated with cold-start NOx emissions. Herein, Cs1Mg3Al catalyst prepared by sol–gel method was cyclic tested in NOx storage under 5 vol% water. At 100 °C, the NOx storage capacity (1219 μmol g−1) was much higher than that of Pt/BaO/Al2O3 (610 μmol g−1). This provided new insights for non-noble metal catalysts in low-temperature passive NOx adsorption. The addition of Cs improved the mobility of oxygen species and thus improved the NOx storage capacity. The XRD, XPS, IR spectra and in situ DRIFTs with NH3 probe showed an interaction between CsOx and AlOx sites via oxygen species formed on Cs1Mg3Al catalyst. The improved mobility of oxygen species inferred from O2-TPD was consistent with high NOx storage capacity related to enhanced formation of nitrate and additional nitrite species by NOx oxidation. Moreover, the addition of Mg might improve the stability of Cs1Mg3Al by stabilizing surface active oxygen species in cyclic experiments.

Cesium vapor thermionic converters are an attractive method of converting high-temperature heat directly to electricity, but theoretical descriptions of the systems have been difficult due to the multi-step ionization of Cs through inelastic electron–neutral collisions. This work presents particle-in-cell simulations of these converters, using a direct simulation Monte Carlo collision model to track 52 excited states of Cs. These simulations show the dominant role of multi-step ionization, which also varies significantly based on both the applied voltage bias and pressure. The electron energy distribution functions are shown to be highly non-Maxwellian in the cases analyzed here. A comparison with previous approaches is presented, and large differences are found in ionization rates due especially to the fact that previous approaches have assumed Maxwellian electron distributions. Finally, an open question regarding the nature of the plasma sheaths in the obstructed regime is discussed. The one-dimensional simulations did not produce stable obstructed regime operation and thereby do not support the double-sheath hypothesis. [ABSTRACT FROM AUTHOR]

The results of the development and research of the technological process for manufacturing spherical vapor cells are presented. Such cells are used in quantum devices, such as magnetometers, gyroscopes, and atomic clocks. Their work is based on optical pumping and detection of the state of alkali metal vapors, in particular cesium. To increase the lifetime of cesium spin polarization in the vapor cell, it is filled with a buffer inert gas. The quality of cell manufacturing directly affects such device characteristics as the width of resonance lines and the achievable signal-to-noise ratio. The proposed cell manufacturing technology simplifies the technological process, eliminates the use of specialized equipment, and increases the reproducibility of results associated with chemical reactions of an alkali metal with foreign impurities in a buffer gas. This is achieved by detecting the formed compounds and excluding them from the composition of the gaseous environment of the cells through the selection of a reasonable sequence of technological operations in the cell manufacturing cycle. The use of traditional methods of X-ray diffraction is associated with the need to depressurize the vapor cell with cesium which leads to the inevitable reaction of cesium with components of the air environment. The work proposes a two-stage analytical assessment of the composition of the gas mixture. At the first stage, the thermodynamic resolution of all possible reactions in the cesium-nitrogen-impurity oxygen system is determined. At the second stage, the color spectrum of the spectra of experimentally obtained reaction products is compared with the color of the products of thermodynamically allowed interactions. Thermodynamic analysis based on a two-stage approach made it possible to identify the formation of cesium suboxides in a vapor cell when it was heated in the temperature range of 273–700 K. To exclude them from the composition of the vapor cell, a sequence of operations was proposed. It involves the formation of an ampoule using the glass blowing method which has a technological cylindrical part and a spherical cell connected to it by a constriction. High purity cesium encapsulated in a glass shell is placed into the technological part of the ampoule, after which the ampoule is evacuated. After opening the capsule with cesium, thermal distillation of pure cesium into a spherical zone takes place. The technological process is completed by filling the cell with buffer gas, after which it is sealed off. The absence of heating during filling a vapor cell with nitrogen significantly simplifies the technological process and minimizes the amount of foreign impurities in the form of cesium suboxides in the gas mixture.

Methods for dose estimation of 137Cs in mouse-like rodents, specifically bank voles (Myodes glareolus), commonly found within the research sites in the Chornobyl Exclusion Zone, are being proposed. The International Commission on Radiological Protection recommends using the specially developed "BiotaDC" software, but it needs to be adapted to solve specific applied issues. It is shown that the "BiotaDC" approach adequately describes dose accumulation of 137Cs for external exposure inside nest chambers if the mean integral value of soil activity concentration at a depth of 0.5 m is used, for external exposure above soil – if the mean integral value of soil activity concentration at a depth of 0.2 m is used. However, the authors propose a method considering the age of animals at the time of capture and the age-related dynamics of changes in such parameters as excretion and accumulation of radioisotopes for internal dose estimation using the "BiotaDC" software. A detailed dose estimation algorithm is being proposed. Dose estimates for internal irradiation according to the authors' method and the method of the International Commission on Radiological Protection are being compared.

A new method for synthesis of metal polyhydrides via high‐pressure thermal decomposition of corresponding amidoboranes in diamond anvil cells is proposed. Within this approach, molecular semiconducting cesium (P4/nmm‐CsH7, P1‐CsH15+x) and rubidium (RbH9‐x) polyhydrides with a very high hydrogen content reaching 93 at.% are synthesized. Preservation of CsH7 at near ambient conditions, confirmed both experimentally and theoretically, represents a significant advance in the stabilization of hydrogen‐rich compounds. In addition, two crystalline modifications of RbH9‐x with pseudohexagonal and pseudotetragonal structures identified by synchrotron X‐ray diffraction, and Raman measurements are synthesized. Both phases are stable at 8–10 GPa. This is an unprecedentedly low stabilization pressure for polyhydrides. These discoveries open up possibilities for modifying existing hydrogen storage materials to increase their efficiency. [ABSTRACT FROM AUTHOR]

The term "light yield" (LY) refers to the ability of scintillator materials to convert high‐energy radiation into visible light. A higher LY corresponds to improved energy and spatial resolution in detectors. The enhancement of scintillator material performance is a crucial aspect of their development. In this study, the Cs2TeCl6 (CTC) double perovskite microcrystals is synthesized, and the broadband yellow emission shows a high degree of matching with the Charge‐coupled Device (CCD). However, the LY of CTC is poor for practical applications in X‐ray imaging. The scintillation performance is significantly enhanced through hafnium alloying. The LY increased from ≈4167 to 38 523 photons/MeV, and the detection limit decreased from 948 to 258 nGy s−1. The underlying mechanism of Te4+ ions emission is systematically explored through density function theory (DFT) analysis, along with investigations into pressure‐dependent photoluminescence, temperature‐dependent photoluminescence, and low‐temperature thermoluminescence. Furthermore, a flexible X‐ray scintillator screen with an outstanding high spatial resolution of 15.9 lp mm−1 is successfully fabricated. This work not only represents a substantial advancement in the scintillation performance of Te4+ ions emission double perovskite microcrystals but also provides an effective strategy for the development of the next generation of halide scintillators. [ABSTRACT FROM AUTHOR]

Hybrid organic-inorganic lead halide perovskites (LHPs) have emerged as a highly significant class of materials due to their tunable and adaptable properties, which make them suitable for a wide range of applications. One of the strategies for tuning and optimizing LHP-based devices is the substitution of cations and/or anions in LHPs. The impact of Cs substitution at the A site on the structural, vibrational, and elastic properties of MAxCs1−xPbCl3-mixed single crystals was investigated using X-ray diffraction (XRD) and Raman and Brillouin light scattering techniques. The XRD results confirmed the successful synthesis of impurity-free single crystals, which exhibited a phase coexistence of dominant cubic and minor orthorhombic symmetries. Raman spectroscopy was used to analyze the vibrational modes associated with the PbCl6 octahedra and the A-site cation movements, thereby revealing the influence of cesium incorporation on the lattice dynamics. Brillouin spectroscopy was employed to investigate the changes in elastic properties resulting from the Cs substitution. The incorporation of Cs cations induced lattice distortions within the inorganic framework, disrupting the hydrogen bonding between the MA cations and PbCl6 octahedra, which in turn affected the elastic constants and the sound velocities. The substitution of the MA cations with smaller Cs cations resulted in a stiffer lattice structure, with the two elastic constants increasing up to a Cs content of 30%. The current findings facilitate a fundamental understanding of mixed lead chloride perovskite materials, providing valuable insights into their structural and vibrational properties. [ABSTRACT FROM AUTHOR]

We developed a new approach for the synthesis of flavanone from chalcones without electrical energy, such as stirring or heating, by using a cesium fluoride–crown ether complex. This "zero electrical energy reaction" is a new category of reaction that has the potential to replace the general organic reaction. [ABSTRACT FROM AUTHOR]

AbstractSafety basis calculations support the safety considerations necessary for legacy nuclear facilities as they transition from active use, through limited operations and standby modes, until final disposition is achieved. Many of the calculations are governed heavily by the coefficients presented in DOE-HDBK-3010 in the form of airborne release of radioactive material resulting from penetration of the facility per seismic activity, full facility fires, and/or explosions. The main objective of this study is to validate the original data for airborne release fractions (ARFs) for powder contaminants under impact, as determined in DOE-HDBK-3010. The limited data available for impact experiments was generated at the Rocky Flats Plant in 1987, where the median ARFs for surrogate powder contamination were 4E-4 with a bounding value of 1E-2. However, estimating the level of uncertainty was challenging in the absence of multiple measurements conducted under identical test conditions. Moreover, the uncertainty was significantly increased due to the restricted range of the test conditions.A more modern approach has been developed for the experimental design in this study, utilizing standardized techniques and analytical instruments. An impact apparatus was employed to be able deliver repeatable impact forces up to 369 kg·cm (320 in.·lb.). Cesium chloride was used as the surrogate powder contaminant in these experiments as it is extremely soluble in water and is even more so in the acidic media used to leach/dissolve the air filters for concentration analysis using mass spectrometry The developed approach leveraged multiple international standards and historical documents in an attempt to recreate a valid testing system that can be used for future analysis and to analyze mitigation factors such as contamination fixative technologies. The current ARFs were found to be consistent with the original values in DOE-HDBK-3010, 3.47E-4 and 4E-4, respectively. [ABSTRACT FROM AUTHOR]

Highly reactive fission product cesium may volatilize at high temperatures. PbO–B 2 O 3 –ZnO glass with low melting temperature and excellent chemical durability can be used as a potential matrix for immobilizing Cs. In this work, five PbO–B 2 O 3 –ZnO glasses with different contents of Pb were synthesized via a melt-quenching process. These specimens were characterized with XRD, Raman, DTA and viscosity measurements. The results showed that the melting temperature decreases, viscosity decreases and structural polymerization increases with increasing lead content. Cs-doped 35PbO–60B 2 O 3 –5ZnO glasses were synthesized at low temperatures. XRD results revealed the amorphous nature of the glass solidified bodies. EDS and ICP-MS studies confirmed that Cs is retained in the glass. Clear vitrified waste products containing up to 13.6 wt% Cs were obtained. The chemical durability of the samples was evaluated via PCT-A and MCC-1 method. For the glass solidified body comprising a Cs/matrix ratio of 0.136, the leaching rate of Cs was 1.6 × 10−1 g m−2 d−1 from the PCT test, which indicates that it has a good chemical stability. 35PbO–60B 2 O 3 –5ZnO glass was expected to be a suitable matrix for Cs immobilization. [ABSTRACT FROM AUTHOR]

The small size and large trap density have seriously hindered the application of cesium copper iodine single crystals (SCs). Herein, we propose a strategy for synthesizing high-quality and large-sized CsCu2I3 SCs by gradient crystallization. The as-synthesized CsCu2I3 SCs exhibit a large length of 1.7 cm with a low trap density of 4.17 × 109 cm−3. Moreover, such CsCu2I3 SCs show excellent photoelectric response to ultraviolet (UV) irradiation, owing to their high absorption coefficient, large Stokes shift, and one-dimensional electronic structure. The measured responsivity and detectivity of the CsCu2I3 SC-based photodetectors reach the maxima of 24.58 A/W and 1.02 × 1013 Jones, respectively, under 365 nm light irradiation. Due to the outstanding UV detection performance, such photodetectors are also utilized for achieving direct UV imaging with high resolutions. [ABSTRACT FROM AUTHOR]

Inorganic cesium lead halide perovskites (CsPbIxBr3−x, 0≤x≤3) are promising alternatives with great thermal stability. Additionally, the choice of moisture‐resistive and dopant‐free carbon as the electrode material can simultaneously solve the problems of stability and cost. Therefore, carbon electrode‐based inorganic PSCs (C‐IPSCs) represent a promising candidate for commercialization, yet both the efficiencies and stability of related devices demand further progress. This article reviews the recent advancement of C‐IPSCs and then unravels the distinctive merits and limitations in this field. Subsequently, our perspective on various modification strategies is analyzed on a methodological level. Finally, this article outlooks the promising research contents and the remaining unresolved issues in this field. We believe that understanding and analyzing the related problems in this field are instructive to stimulate the future development of C‐IPSCs. [ABSTRACT FROM AUTHOR]