bluuebunny/crossref_metadata_2025_split huggingface dataset:
Relationship between personal-sampled air lead and blood lead in low-lead-exposure workers in Japan to apply multiple regression models determining permissible air lead concentration
Authors: Ono Akira , Horiguchi Hyogo 
Published: August 2021

Abstract

Objectives
We investigated the relationship between lead in air (Pb-A) measured by personal sampling and blood lead (Pb-B) in workers with relatively low lead exposure to estimate the permissible air concentration of lead corresponding to the biological tolerance value of Pb-B of 15 µg/dL.

Methods
We collected air samples at a lead-acid battery factory in Japan by personal sampling devices attached to 32 workers (19 males and 13 females) and measured Pb-A by a graphite furnace atomic absorption spectrophotometer in 2017-2020. In addition, we collected information on age, smoking habits, Pb-B, and urinary δ-aminolevulinic acid from the records of medical examinations for lead poisoning. Samples were collected two times from four workers, resulting in 36 data sets.

Results
Before analyses, we excluded four inappropriate data sets. The levels of Pb-A in the factory and Pb-B in the workers were almost under the current permissible limits. Multiple regression models showed significant correlations between Pb-B and Pb-A, and sex, and borderline significance between Pb-B and age. Based on them, we calculated Pb-A corresponding to Pb-B 15 μg/dL, and obtained similar values to the current occupational exposure limit (OEL) of 30 μg/m3, with slight variation between sex and age.

Conclusion
These results validate OEL, although supplementary conditions in terms of sex and age may be necessary.
How does CBCT reconstruction algorithm impact on deformably mapped targets and accumulated dose distributions?
Authors: Mao Weihua , Liu Chang , Gardner Stephen J. , Elshaikh Mohamed , Aref Ibrahim , Lee Joon K. , Pradhan Deepak , Siddiqui Farzan , Snyder Karen Chin , Kumarasiri Akila , Zhao Bo , Kim Joshua , Li Haisen , Wen Ning Winston , Movsas Benjamin , Chetty Indrin J. 
Published: August 2021

AbstractPurposeWe performed quantitative analysis of differences in deformable image registration (DIR) and deformable dose accumulation (DDA) computed on CBCT datasets reconstructed using the standard (Feldkamp‐Davis‐Kress: FDK_CBCT) and a novel iterative (iterative_CBCT) CBCT reconstruction algorithms.MethodsBoth FDK_CBCT and iterative_CBCT images were reconstructed for 323 fractions of treatment for 10 prostate cancer patients. Planning CT images were deformably registered to each CBCT image data set. After daily dose distributions were computed, they were mapped to planning CT to obtain deformed doses. Dosimetric and image registration results based CBCT images reconstructed by two algorithms were compared at three levels: (A) voxel doses over entire dose calculation volume, (B) clinical constraint results on targets and sensitive structures, and (C) contours propagated to CBCT images using DIR results based on three algorithms (SmartAdapt, Velocity, and Elastix) were compared with manually delineated contours as ground truth.Results(A) Average daily dose differences and average normalized DDA differences between FDK_CBCT and iterative_CBCT were ≤1 cGy. Maximum daily point dose differences increased from 0.22 ± 0.06 Gy (before the deformable dose mapping operation) to 1.33 ± 0.38 Gy after the deformable dose mapping. Maximum differences of normalized DDA per fraction were up to 0.80 Gy (0.42 ± 0.19 Gy). (B) Differences in target minimum doses were up to 8.31 Gy (−0.62 ± 4.60 Gy) and differences in critical structure doses were 0.70 ± 1.49 Gy. (C) For mapped prostate contours based on iterative_CBCT (relative to standard FDK_CBCT), dice similarity coefficient increased by 0.10 ± 0.09 (p < 0.0001), mass center distances decreased by 2.5 ± 3.0 mm (p < 0.00005), and Hausdorff distances decreased by 3.3 ± 4.4 mm (p < 0.00015).ConclusionsThe new iterative CBCT reconstruction algorithm leads to different mapped volumes of interest, deformed and cumulative doses than results based on conventional FDK_CBCT.
Visualizing Quasi‐Static Electric Fields with Flexible and Printed Organic Transistors
Authors: Shoji Itsuki , Wada Hideki , Uto Kodai , Takeda Yasunori , Sugimoto Toshiyuki , Matsui Hiroyuki 
Published: August 2021

AbstractUnlike electromagnetic radiation such as radio waves, infrared‐visible‐ultraviolet, and X‐rays, static or quasi‐static electric fields are rarely utilized for visualization in people's lives and industries. The difficulty in measuring quasi‐static electric fields is mainly due to low‐energy photons and the lack of integrable devices with high sensitivity to detect them. Here, a novel quasi‐static electric field sensor based on a floating extended gate organic field‐effect transistor is shown, which is highly sensitive, integrable as an array, ultra‐flexible, highly expandable, and digitally printable. The sensor has a thickness of ≈2 µm and can detect the proximity to human hands with low static electricity at a distance of tens of centimeters. The sensor can provide a new vision of electric charges, proximity sensing capability, and, in the future, a noncontact method for measuring biological activities such as brain waves.
Model‐based design of experiments for polyether production from bio‐based 1,3‐propanediol
Authors: Vo Anh‐Duong Dieu , Shahmohammadi Ali , McAuley Kimberley B. 
Published: August 2021

AbstractSequential model‐based design of experiments (MDBOE) accounts for information from previous experiments when selecting conditions for new experiments. In the current study, sequential MBDOE is used to select operating conditions for experiments in a batch‐reactor that produces bio‐based polytrimethylene ether glycol (PO3G). These Bayesian A‐optimal experiments are designed to obtain improved estimates of 70 fundamental‐model parameters, while accounting for industrial data from eight previous runs. Settings are selected for three decision variables: reactor temperature, initial catalyst level, and initial water concentration. If only one new experiment is conducted, it should be run at high temperature, with relatively high concentrations of catalyst and initial water. When two new runs are conducted, one should use an intermediate catalyst concentration. The effectiveness of the proposed MBDOE approach is tested using Monte‐Carlo simulations, revealing that the selected experiments are superior compared to experiments selected randomly from corners of the permissible design space.
Compositional and kinetic study of thermal degradation of kerogen using TG‐FTIR, NMR, and microscopic study
Authors: Baruah Bhargav , Tiwari Pankaj 
Published: August 2021

AbstractUnderstanding the thermal maturation mechanism of kerogen has both industrial and scientific significance. Here, kerogen extracted from Indian oil shale of Upper Assam basin is subjected to TG‐FTIR analysis to study the thermal decomposition behavior of isolated kerogen and compared with oil shale sample. Kinetic study of kerogen was performed on thermogravimetric data using isoconversional methods. The mean apparent activation energy values were found in the range of 219 to 236 kJ/mol. The reaction models were identified as first‐order and A2 nucleation models. The obtained kinetic parameters were validated by reconstruction of conversion profiles. Comparison of oil derived from kerogen with shale oil, and solvent‐extracted bitumen using NMR analysis showed that kerogen initially matures into bitumen, and thereafter, gets converted to oil and gas in the presence of inherent minerals. The predicted degradation mechanisms of kerogen from the parent oil shale sample were examined using microscopic study.
Ionic Liquid Functionalized Gel Polymer Electrolytes for Stable Lithium Metal Batteries
Authors: Zhou Tianhong , Zhao Yan , Choi Jang Wook , Coskun Ali 
Published: August 2021

AbstractMetallic lithium (Li) is regarded as the ideal anode material in lithium‐ion batteries due to its low electrochemical potential, highest theoretical energy density and low density. There are, however, still significant challenges to be addressed such as Li‐dendrite growth and low interfacial stability, which impede the practical application of Li metal anodes. In order to circumvent these shortcomings, herein, we present a gel polymer electrolyte containing imidazolium ionic liquid end groups with a perfluorinated alkyl chain (F‐IL) to achieve both high ionic conductivity and Li ion transference number by fundamentally altering the solubility of salt within the gel electrolyte through Lewis‐acidic segments in the polymer backbone. Moreover, the presence of F‐IL moieties decreased the binding affinity of Li cation towards the glycol chains, enabling a rapid transfer of Li cation within the gel network. These structural features enabled the immobilization of anions on the ionic liquid segments to alleviate the space‐charge effect while promoting stronger anion coordination and weaker cation coordination in the Lewis‐acidic polymers. Accordingly, we realized a high Li ion conductivity (9.16×10−3 S cm−1) and high Li ion transference number of 0.69 simultaneously, along with a good electrochemical stability up to 4.55 V, while effectively suppressing Li dendrite growth. Moreover, the gel polymer electrolyte exhibited stable cycling performance of the Li|Li symmetric cell of 9 mAh cm−2 for more than 1800 hours and retained 86.7 % of the original capacity after 250 cycles for lithium‐sulfur (Li‐S) full cell.
Identifizierung von RNA‐Basenpaaren und vollständige Zuordnung von Nukleobasen‐Resonanzen durch Protonen‐detektierte Festkörper‐NMR‐Spektroskopie bei MAS Geschwindigkeiten von 100 kHz
Authors: Aguion Philipp Innig , Kirkpatrick John , Carlomagno Teresa , Marchanka Alexander 
Published: August 2021

AbstractDie Aufklärung von RNA Strukturen, entweder in Isolation oder im Komplex, ist essentiell, um die Mechanismen zellulärer Prozesse zu verstehen. Festkörper‐NMR ist auf Komplexe mit hohem Molekulargewicht anwendbar und benötigt keine Kristallisation; Die Methode ist daher gut geeignet um RNA als Teil von großen mehrkomponentigen Komplexen zu untersuchen. Kürzlich konnten wir die ersten Strukturen von RNA und einem RNA‐Protein Komplex mittels Festkörper‐NMR durch die Anwendung von konventioneller 13C‐ und 15N‐Detektion lösen. Dieser Ansatz ist durch diverse RNA Peak‐Überlappungen und die niedrige Intensität von multidimensionalen Experimenten limitiert. In dieser Arbeit überwinden wir die Limitationen in Sensitivität und Auflösung durch die Anwendung von 1H‐Detektion bei schnellen MAS Geschwindigkeiten. Wir entwickeln Experimente, die die Identifizierung von vollständigen Spinsystemen der Nukleobasen zusammen mit derer Nukleotid‐spezifischer Basenpaarung ermöglichen. Diese Experimente benötigen weniger als ein Milligramm einer uniform Isotopen‐markierten RNA Probe und erlauben die schnelle Bestimmung der RNA Sekundärstruktur durch Festkörper‐NMR in Protein‐RNA Komplexen jedweder Größe.
Microporous Carbon Nitride (C3N5.4) with Tetrazine based Molecular Structure for Efficient Adsorption of CO2 and Water
Authors: Sathish CI , Premkumar S. , Chu Xueze , Yu Xiaojiang , Breese Mark B. H. , Al‐Abri Mohammed , Al‐Muhtaseb Ala'a H. , Karakoti Ajay , Yi Jiabao , Vinu Ajayan 
Published: August 2021

AbstractMesoporous carbon nitrides with C3N5 and C3N6 stoichiometries created a new momentum in the field of organic metal‐free semiconductors owing to their unique band structures and high basicity. Here, we report on the preparation of a novel graphitic microporous carbon nitride with a tetrazine based chemical structure and the composition of C3N5.4 using ultra‐stable Y zeolite as the template and aminoguanidine hydrochloride, a high nitrogen‐containing molecule, as the CN precursor. Spectroscopic characterization and density functional theory calculations reveal that the prepared material exhibits a new molecular structure, which comprises two tetrazines and one triazine rings in the unit cell and is thermodynamically stable. The resultant carbon nitride shows an outstanding surface area of 130.4 m2 g−1 and demonstrates excellent CO2 adsorption per unit surface area of 47.54 μmol m−2, which is due to the existence of abundant free NH2 groups, basic sites and microporosity. The material also exhibits highly selective sensing over water molecules (151.1 mmol g−1) and aliphatic hydrocarbons due to its unique microporous structure with a high amount of hydrophilic nitrogen moieties and recognizing ability towards small molecules.
Stabilizing Transition Metal Vacancy Induced Oxygen Redox by Co2+/Co3+ Redox and Sodium‐Site Doping for Layered Cathode Materials
Authors: Li Xun‐Lu , Bao Jian , Shadike Zulipiya , Wang Qin‐Chao , Yang Xiao‐Qing , Zhou Yong‐Ning , Sun Dalin , Fang Fang 
Published: August 2021

AbstractAnionic redox is an effective way to boost the energy density of layer‐structured metal‐oxide cathodes for rechargeable batteries. However, inherent rigid nature of the TMO6 (TM: transition metals) subunits in the layered materials makes it hardly tolerate the inner strains induced by lattice glide, especially at high voltage. Herein, P2‐Na0.8Mg0.13[Mn0.6Co0.2Mg0.07□0.13]O2 (□: TM vacancy) is designed that contains vacancies in TM sites, and Mg ions in both TM and sodium sites. Vacancies make the rigid TMO6 octahedron become more asymmetric and flexible. Low valence Co2+/Co3+ redox couple stabilizes the electronic structure, especially at the charged state. Mg2+ in sodium sites can tune the interlayer spacing against O‐O electrostatic repulsion. Time‐resolved in situ X‐ray diffraction confirms that irreversible structure evolution is effectively suppressed during deep desodiation benefiting from the specific configuration. X‐ray absorption spectroscopy (XAS) and density functional theory (DFT) calculations demonstrate that, deriving from the intrinsic vacancies, multiple local configurations of “□‐O‐□”, “Na‐O‐□”, “Mg‐O‐□” are superior in facilitating the oxygen redox for charge compensation than previously reported “Na‐O‐Mg”. The resulted material delivers promising cycle stability and rate capability, with a long voltage plateau at 4.2 V contributed by oxygen, and can be well maintained even at high rates. The strategy will inspire new ideas in designing highly stable cathode materials with reversible anionic redox for sodium‐ion batteries.
Mechanistic Insights into the Formation of the 6,10‐Bicyclic Eunicellane Skeleton by the Bacterial Diterpene Synthase Bnd4
Authors: Xu Baofu , Tantillo Dean J. , Rudolf Jeffrey D. 
Published: August 2021

AbstractThe eunicellane diterpenoids are a unique family of natural products seen in marine organisms, plants, and bacteria. We used a series of biochemical, bioinformatics, and theoretical experiments to investigate the mechanism of the first diterpene synthase known to form the eunicellane skeleton. Deuterium labeling studies and quantum chemical calculations support that Bnd4, from Streptomyces sp. (CL12‐4), forms the 6,10‐bicyclic skeleton through a 1,10‐cyclization, 1,3‐hydride shift, and 1,14‐cyclization cascade. Bnd4 also demonstrated sesquiterpene cyclase activity and the ability to prenylate small molecules. Bnd4 possesses a unique D94NxxxD motif and mutation experiments confirmed an absolute requirement for D94 as well as E169.
Enabling the Use of Alkyl Thianthrenium Salts in Cross‐Coupling Reactions by Copper Catalysis
Authors: Chen Cheng , Wang Minyan , Lu Hongjian , Zhao Binlin , Shi Zhuangzhi 
Published: August 2021

AbstractAlkyl groups are one of the most widely used groups in organic synthesis. Here, a a series of thianthrenium salts have been synthesized that act as reliable alkylation reagents and readily engage in copper‐catalyzed Sonogashira reactions to build C(sp3)−C(sp) bonds under mild photochemical conditions. Diverse alkyl thianthrenium salts, including methyl and disubstituted thianthrenium salts, are employed with great functional breadth, since sensitive Cl, Br, and I atoms, which are poorly tolerated in conventional approaches, are compatible. The generality of the developed alkyl reagents has also been demonstrated in copper‐catalyzed Kumada reactions.
Photocatalytic selective oxidation of HMF to DFF over Bi2WO6/mpg–C3N4 composite under visible light
Authors: Cheng Lili , Huang Danyao , Zhang Yun , Wu Ying 
Published: August 2021

Bi2WO6/mpg–C3N4 composite catalyst was prepared by hydrothermal method and applied in the partial oxidation of HMF to DFF by photocatalytic approach. The 12% Bi2WO6/mpg–C3N4 composite exhibits the highest catalytic performance, with the HMF conversion of 59.3% and the DFF selectivity of 84.3% after 6 h. This may be primarily ascribed to the synergetic effect of Bi2WO6 and mpg–C3N4 on photogenerated charges separation through the charge transfer between the two semiconductors. Based on the reactive species trapping experiment, it is concluded that ·O2− plays a significant part to convert HMF into DFF and the electron–hole separation follows a Z‐scheme mechanism.
Silver nanoparticles supported on smart polymer microgel system for highly proficient catalytic reduction of Cr+6 to Cr+3 with formic acid
Authors: Hussain Iftikhar , Ali Faisal , Shahid Muhammad , Begum Robina , Irfan Ahmad , Wu Weitai , Shaukat Saadia , Farooqi Zahoor H. 
Published: August 2021

AbstractPoly(styrene@N‐isopropylmethacrylamide‐methacrylic acid) [P (St‐NM)] microgels were prepared via seed facilitated emulsion polymerization process. In situ reduction of silver ions was carried out to generate Ag nanoparticles in the voids of shell region of polymer microgels. Synthesized P (St‐NM) and Ag‐P (St‐NM) particles were characterized by UV–Vis spectroscopy, transmission electron microscopy (TEM), Fourier‐transformed infrared spectroscopy (FTIR), and X‐ray diffraction (XRD). The stability of Ag nanoparticles within P (St‐NM) system over the wide range of pH and temperature is also a part of this study. Thus, prepared Ag‐P (St‐NM) was tested for its catalytic efficiency against reduction of K2Cr2O7 using formic acid (FA) as reductant. Factors affecting catalytic efficiency of Ag‐P (St‐NM) system towards transformation of Cr+6 to Cr+3 were investigated. Other toxic chemicals can also be reduced using same catalytic system.
Preliminary evidence of an endangered species benefiting from moderate climate warming: A palaeolimnological study of the charophyte Lychnothamnus barbatus
Authors: Brzozowski Michał , Kowalewski Grzegorz , Szczuciński Witold , Kaczmarek Lech , Pełechaty Mariusz 
Published: August 2021

Abstract

In a time of rapid environmental changes, identification of the effects of climate warming on charophytes (Characeae, Charophyta) will enable the optimization of conservation measures, especially for extremely rare species. Lychnothamnus barbatus is one of the rarest charophytes worldwide, which has decreased in the number of occupied sites over the last century. However, the recolonization of former sites has been observed in recent years (e.g. Lake Kuźnickie, Poland). The study aimed to analyse the effects of climatic changes and human pressure on the L. barbatus population.
Three 30 cm sediment cores were collected from minimum, average, and maximum depths of L. barbatus occurrence to determine the past vegetation composition. Sediment cores were dated using the radioisotopes lead‐210, caesium‐137, and carbon‐14. A spatial analysis of the lake catchment changes during the last 120 years was also conducted.
The study demonstrated L. barbatus presence in Lake Kuźnickie at the beginning of the 16th century. However, a sharp increase in the proportion of this species in the vegetation community occurred in the 19th century and during climate warming at the end of the Little Ice Age. Factors that significantly influenced the present occurrence of the L. barbatus population included improvement in water quality and the oospore bank deposited in the bottom sediments.
This study is the first palaeoreconstruction in a modern lake dominated by L. barbatus. Based on the history of L. barbatus in Lake Kuźnickie after the end of the Little Ice Age, the positive effect of climate warming on the contemporary recovery of this charophyte is postulated.
The reaction of L. barbatus to climate warming appears to differ from commonly accepted scenarios for aquatic macrophytes because its recovery in the past and at present coincided with increases in air temperature. This research indicated the appropriate management and conservation practices for lakes with L. barbatus populations.
Diversity of Luminescent Metal Complexes in OLEDs: Beyond Traditional Precious Metals
Authors: Li Xiaoning , Xie Yujun , Li Zhen 
Published: August 2021

AbstractOrganic light‐emitting diodes (OLED) have attracted increasing attention due to their excellent properties, such as self‐luminosity, high color gamut and flexibility, and potential applications in display, wearable devices and lighting. The emitters are the most important composition in OLEDs, mainly classified into fluorescent compounds (first generation), metal phosphorescent complexes (second generation), and thermally activated delayed fluorescence (TADF) materials (third generation). In this review, we summarize the advances of novel emitters of organic metal complexes in the last decade, focusing on coinage metals (Cu, Ag, and Au) and non‐precious metals (Al, Zn, W, and alkali metal). Also, the design strategy of d10 and Au(III) complexes was discussed. We aim to provide guidance for exploring efficient metal complexes beyond traditional phosphorescent complexes.
The Origin of Gaseous Decomposition Products Formed During SEI Formation Analyzed by Isotope Labeling in Lithium‐Ion Battery Electrolytes
Authors: Leißing Marco , Peschel Christoph , Horsthemke Fabian , Wiemers‐Meyer Simon , Winter Martin , Nowak Sascha 
Published: August 2021

AbstractInterphase formation during the first charge and discharge cycle(s) of a battery cell is among the least understood processes in lithium‐ion batteries (LIBs). The formation of interphases is a result of electrolyte decomposition and accompanied by gassing. The direct analysis of these interphases is challenging and indirect methods are required to obtain information about this process. For example, indirect, ex situ analyses of gaseous decomposition products can help to draw conclusions about occurring reactions in the cell. In this work, the origin of several permanent gases and hydrocarbons (CO, CH4, C2H4 and C2H6) emerging during the formation of LiNi0.6Mn0.2Co0.2O2 (NMC622)||graphite pouch type LIBs equipped with a gas sampling port was investigated. Isotope labeled electrolytes (13C3‐EC, D4‐EC) were used to assign formation gas products to the individual constituents of the electrolyte mixture. The effect of common linear carbonates in combination with ethylene carbonate (EC) as well as the effect of vinylene carbonate (VC) as film forming additive was investigated. The obtained mass spectra from gas chromatography mass spectrometry (GC‐MS) and the mass shift caused by the labeled electrolyte components, enabled an assignment of individual electrolyte components to the resulting gas products. The aim of this work is to gain more information about interphase reactions and thus to improve understanding of the mechanisms behind formation.