bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tailoring the Electronic Structure of an Atomically Dispersed Zinc Electrocatalyst: Coordination Environment Regulation for High Selectivity Oxygen Reduction
Authors: Jia Yaling , Xue Ziqian , Yang Jun , Liu Qinglin , Xian Jiahui , Zhong Yicheng , Sun Yamei , Zhang Xiuxiu , Liu Qinghua , Yao Daoxin , Li Guangqin 
Published: October 2021

AbstractAccurately regulating the selectivity of the oxygen reduction reaction (ORR) is crucial to renewable energy storage and utilization, but challenging. A flexible alteration of ORR pathways on atomically dispersed Zn sites towards high selectivity ORR can be achieved by tailoring the coordination environment of the catalytic centers. The atomically dispersed Zn catalysts with unique O‐ and C‐coordination structure (ZnO3C) or N‐coordination structure (ZnN4) can be prepared by varying the functional groups of corresponding MOF precursors. The coordination environment of as‐prepared atomically dispersed Zn catalysts was confirmed by X‐ray absorption fine structure (XAFs). Notably, the ZnN4 catalyst processes a 4 e− ORR pathway to generate H2O. However, controllably tailoring the coordination environment of atomically dispersed Zn sites, ZnO3C catalyst processes a 2 e− ORR pathway to generate H2O2 with a near zero overpotential and high selectivity in 0.1 M KOH. Calculations reveal that decreased electron density around Zn in ZnO3C lowers the d‐band center of Zn, thus changing the intermediate adsorption and contributing to the high selectivity towards 2 e− ORR.
Photokatalytische gem‐Difluorolefinierungsreaktionen durch eine formale C−C‐Kupplungs/Defluorierungsreaktion mit Diazoacetaten
Authors: Li Fang , Pei Chao , Koenigs Rene M. 
Published: October 2021

AbstractDie Photolyse von Diazoalkanen zur Durchführung von Singulett‐Carbentransferreaktionen gefärbter Diazoalkane hat in letzter Zeit großes Interesse in der organischen Synthese geweckt. Hier beschreiben wir einen photokatalytischen Ansatz, der den Zugang zu Triplettcarbenen über Energietransfer ermöglicht, um hocheffiziente gem‐Difluorolefinierungsreaktionen mit α‐Trifluormethylstyrolen durchzuführen. Die Verwendung eines tertiären Amins erwies sich als entscheidend, um diesen ungewöhnlichen Reaktionsweg zu erschließen und unerwünschte Cyclopropanierungsreaktionen zu verhindern. Das Amin erleichtert zudem die finale Abstraktion von Fluorid zum gem‐Difluorolefinen (43 Beispiele, bis zu 88 % Ausbeute), was durch experimentelle und theoretische mechanistische Studien gestützt wird. Wir haben diese Synthesemethode mit einem breiten Substratspektrum untersucht, das von einfachen Olefinen und heterocyclischen Olefinen bis hin zur Funktionalisierung pharmazeutisch relevanter Bausteine reicht.
Anthraquinone Covalent Organic Framework Hollow Tubes as Binder Microadditives in Li−S Batteries
Authors: Guo Can , Liu Ming , Gao Guang‐Kuo , Tian Xi , Zhou Jie , Dong Long‐Zhang , Li Qi , Chen Yifa , Li Shun‐Li , Lan Ya‐Qian 
Published: October 2021

AbstractThe exploration of new application forms of covalent organic frameworks (COFs) in Li−S batteries that can overcome drawbacks like low conductivity or high loading when typically applied as sulfur host materials (mostly ≈20 to ≈40 wt % loading in cathode) is desirable to maximize their low‐density advantage to obtain lightweight, portable, or high‐energy‐density devices. Here, we establish that COFs could have implications as microadditives of binders (≈1 wt % in cathode), and a series of anthraquinone‐COF based hollow tubes have been prepared as model microadditives. The microadditives can strengthen the basic properties of the binder and spontaneously immobilize and catalytically convert lithium polysulfides, as proved by density functional calculations, thus showing almost doubly enhanced reversible capacity compared with that of the bare electrode.
Planar Chirality: A Mine for Catalysis and Structure Discovery
Authors: López Rosa , Palomo Claudio 
Published: October 2021

AbstractPlanar chirality is one of the most fascinating expressions of chirality, which is exploited by nature to lock three‐dimensional chiral conformations and, more recently, by chemists to create new chiral reagents, catalysts, and functional organic materials. Nevertheless, the shortage of procedures able to induce and secure asymmetry during the generation of these unique chiral entities has dissuaded chemists from exploiting their structural properties. This Minireview intends to illustrate the limited but remarkable catalytic methods that have been reported for the production of planar chirality in strained molecules and serve as a source of inspiration for the development of new unconventional procedures, which are expected to appear in the near future.
Maximizing Electroactive Sites in a Three‐Dimensional Covalent Organic Framework for Significantly Improved Carbon Dioxide Reduction Electrocatalysis
Authors: Han Bin , Jin Yucheng , Chen Baotong , Zhou Wei , Yu Baoqiu , Wei Chuangyu , Wang Hailong , Wang Kang , Chen Yanli , Chen Banglin , Jiang Jianzhuang 
Published: October 2021

AbstractSynthesis of functional 3D COFs with irreversible bond is challenging. Herein, 3D imide‐bonded COFs were constructed via the imidization reaction between phthalocyanine‐based tetraanhydride and 1,3,5,7‐tetra(4‐aminophenyl)adamantine. These two 3D COFs are made up of interpenetratedptsnetworks according to powder X‐ray diffraction and gas adsorption analyses. CoPc‐PI‐COF‐3 doped with carbon black has been employed to fabricate the electrocatalytic cathode towards CO2reduction reaction within KHCO3aqueous solution, displaying the Faradaic efficiency of 88–96 % for the CO2‐to‐CO conversion at the voltage range of ca. −0.60 to −1.00 V (vs. RHE). In particular, the 3D porous structure of CoPc‐PI‐COF‐3 enables the active electrocatalytic centers occupying 32.7 % of total cobalt‐phthalocyanine subunits, thus giving a large current density (jCO) of −31.7 mA cm−2at −0.90 V. These two parameters are significantly improved than the excellent 2D COF analogue (CoPc‐PI‐COF‐1, 5.1 % and −21.2 mA cm−2).
Pullulan/polyHEMA cryogels: Synthesis, physicochemical properties, and cell viability
Authors: Ustürk Selma , Altundag Ergul Mutlu , Yilmaz Elvan 
Published: October 2021

AbstractPullulan/polyHEMA cryogels were synthesized using epichlorohydrin (ECH) and ethylene glycol dimethacrylate (EGDMA) as crosslinkers. The dried cryogels were characterized by FTIR spectroscopy for chemical structure. Thermal analysis provided evidence for different microstructures of the samples synthesized. Water contact angle (WCA) value measured as 80.56° for the pullulan/ECH/polyHEMA/polyEGDMA IPN sample reveal a more hydrophobic surface compared to the pullulan/ECH/polyHEMA graft copolymer with 18.32° WCA. Scanning electron microscopy analysis of the IPN sample gives an average pore size 72.6 μm, while the graft copolymer contains pores of average size of 100.5 μm. Swelling and degradation kinetics studied by gravimetric method reveal that the samples act as degradable hydrogels in aqueous media with equilibrium swelling capacities of 75%–100% at pH 7.4. Cell viability of pullulan/ECH/polyHEMA/polyEGDMA IPN cryogel for colon carcinoma cell lines (HCT‐116) investigated by MTT assay demonstrate that it is non‐toxic and allows cell proliferation with 159 ± 25.52% cell viability in 9 days.
Incorporation of alkyl‐functionalized silica nanoparticles into hydrophilic epoxy and hydrophobic polystyrene matrices
Authors: Lee Bo‐Young , Park Seoungju , Chung Dae‐Won , Jang Keon‐Soo 
Published: October 2021

AbstractThe homogeneous dispersion of nanosized fillers in a polymeric matrix is crucial for improving the mechanical and thermal properties of composites. In this study, the dispersity of silica nanoparticles (SNPs) in the hydrophilic epoxy and hydrophobic polystyrene (PS) matrices was examined. As the unmodified SNPs were hydrophilic, they dispersed well in the epoxy matrix, but agglomerated in the PS matrix. We also explored the effects of different aliphatic chain lengths (hydrophilic vs. hydrophobic: unmodified, methyl, propyl, and octyl) on the dispersity of nanoparticles in the polymer. The alkyl‐functionalized SNPs were more uniformly dispersed than the unmodified SNPs in the PS matrix. Comparing the different alkyl chains, the propyl‐functionalized SNPs exhibited the most homogeneous dispersion in the polymer, thereby increasing the mechanical properties. The octyl‐functionalized SNPs agglomerated slightly, which might be due to their chain interaction (entanglement). The size of SNPs was controlled (60, 120, and 180 nm) via sol–gel synthesis, and the SNP with the smallest diameter (60 nm) showed the slight enhancement in mechanics and dispersion compared with SNPs with diameters of 120 and 180 nm. The SNP size, hydrophilicity, functionality, and aliphatic chain length on SNP surfaces investigated in this study can be useful for various nanocomposite applications.
Rational Design of Chrysene‐Based Hybridized Local and Charge‐Transfer Molecules as Efficient Non‐Doped Deep‐Blue Emitters for Simple‐Structured Electroluminescent Devices
Authors: Chawanpunyawat Thanyarat , Chasing Pongsakorn , Nalaoh Phattananawee , Maitarad Phornphimon , Sudyodsuk Taweesak , Promarak Vinich 
Published: October 2021

AbstractHerein, we present a molecular design of chrysene‐based deep‐blue emissive materials (TC, TpPC, TpXC, and TmPC), in which chrysene as a core is functionalized with different triphenylamine moieties to realize a fine‐tuning deep‐blue fluorescence with superior electroluminescent (EL) performance. The photophysical analyses and density functional theory (DFT) calculations disclose that TC, TpPC, and TpXC possess HLCT characteristics with intense deep‐blue emission in the solid‐state, good hole‐transporting ability, and high thermal and electrochemical stabilities. They are successfully employed as non‐doped emitters in simple structured OLEDs (ITO/PEDOT : PSS : NF/emitter/TPBi/LiF : Al). In particular, TC‐based device emits a deep‐blue light with an emission peak at 446 nm and CIE color coordinates of (0.148, 0.096), a maximum external quantum efficiency (EQEmax) of 4.31%, and a low turn‐on voltage of 2.8 V.
Gram‐scale synthesis of nitrogen‐doped carbon dots from locusts for selective determination of sunset yellow in food samples
Authors: Su Ke , Xiang Guoqiang , Jin Xinrong , Wang Xin , Jiang Xiuming , He Lijun , Zhao Wenjie , Sun Yaming , Cui Chen 
Published: October 2021

AbstractLocust powder was converted into water‐soluble fluorescent nitrogen‐doped carbon dots (N‐CDs) with gram‐scale yield through a self‐exothermic reaction between nitric acid and diethylenetriamine (DETA) within 10 min. The morphology, elemental information, and optical properties of the N‐CDs were characterized using high‐resolution transmission electron microscopy, X‐ray photoelectron spectroscopy, and Fourier‐transform infrared, ultraviolet–visible and fluorescence spectroscopy. Spectroscopic investigation indicated that the fluorescence emission behaviour of N‐CDs is excitation wavelength dependent, with the strongest emission peak at 470 nm using a 390 nm excitation wavelength. The strong absorption peak of sunset yellow (SY) at 482 nm overlaps substantially with the blue emission peak (470 nm) of N‐CDs. This enables the fluorescence emission of N‐CDs to be obviously quenched by SY through the inner filter effect. There was a good linear relationship between the fluorescence quenching degree and the concentrations of SY within the range 0.5–40 μM. The detection limit of developed fluorescence assay for SY is 28 nM, and the relative standard deviation is 2.3% (c = 10 μM). The N‐CDs derived from locusts by the self‐exothermic reaction are highly selective and sensitive fluorescent probes for SY, which were applied to the fluorescence sensing of SY in different food samples with satisfactory results.
On the Savéant's Concerted/Stepwise Model. The Electroreduction of Halogenated Naphthalene Derivatives as a Case Study
Authors: Stefani Andrea , Giurlani Walter , Bonechi Marco , Marchetti Andrea , Preda Giovanni , Pasini Dario , Innocenti Massimo , Fontanesi Claudio 
Published: October 2021

AbstractThe electroreduction mechanism of 1‐Br‐2‐naphtol and 1‐I‐2‐naphtol, and of two inherently chiral BINOL derivatives ([1,1′‐Binaphthalene]‐2,2′‐diol, 6,6′‐dibromo and 1,1′‐Binaphthalene,6,6′‐dibromo‐2,2′‐dimethoxy; in the following named P1 and P2, respectively), is characterized by means of an integrated electrochemical and theoretical approach. The experimental characterization is based on cyclic voltammetry measurements. The experimental results indicate that the carbon halogen bond dissociates, following the electron uptake, with the formation of an insoluble final product (electro‐polymerization). The reduction mechanism is assessed and disassembled at a molecular level by using DFT based quantum mechanical calculations. Both steady state, equilibrium, and kinetic (molecular dynamics, MD, DRC calculations) properties are calculated. A consistent picture is obtained by the comparison between experimental and theoretical results, indicating that the carbon‐halogen bond dissociates following the first electron uptake, with a stepwise mechanism.
A stabilized finite volume element method for solving Poisson–Nernst–Planck equations
Authors: Li Jiao , Ying Jinyong 
Published: October 2021

AbstractOne difficulty in solving the Poisson–Nernst–Planck (PNP) equations used for studying the ion transport in channel proteins is the possible convection‐dominant problem in the Nernst–Planck equations. In this paper, to overcome this issue, considering the general mixed boundary conditions of concentration functions on the interface, a novel stabilized finite volume element method based on the standard weak formulation to solve the steady‐state PNP equations is proposed and analyzed. Numerical tests on four ion‐channel proteins served as benchmark with varying boundary conditions in a certain range show that the new stabilized technique not only improves the robustness of the new PNP solver, but also makes the computed (especially the maximal) concentration values much more reasonable.
Limited‐transpiration rate and plant conductance in a diverse sweet corn population
Authors: Jafarikouhini Nahid , Sinclair Thomas R. , Resende Marcio F. R. 
Published: October 2021

AbstractLimited‐transpiration rate at elevated vapor pressure deficit (VPD) can allow soil water conservation for use during late‐season drought, but it can also result in decreased crop yields under well‐watered conditions because of restricted crop gas exchange. Previous studies with sweet corn (Zea mays L.) have found the limited‐transpiration rate was quite common among commercial cultivars even though sweet corn is commonly grown under well‐watered conditions. This study was undertaken to identify possible genetic sources of sweet corn that were not encumbered by the limited‐transpiration trait. Additionally, data were obtained to compare the plant hydraulic conductance among the lines. Among the 26 sweet corn lines included in this study, only eight did not express the limited‐transpiration trait. Four of the lines not expressing the limited‐transpiration (IL395a, IL543c, P39, and SD245) had stomata vapor conductance values over the range of tested VPD similar to the values expressed by many of the limited‐transpiration lines only at low VPD. The eight lines not expressing the limited‐transpiration trait tended to have low plant hydraulic conductance. For those lines expressing the limited‐transpiration trait, there was a correlation between the VPD at initiation of limited transpiration and plant hydraulic conductance. Expression of the limited‐transpiration traits proved, however, to be temperature sensitive in 7 of 18 tested lines expressing the trait at 32 °C because they failed to express the trait at 38 °C. The genetic variation in expression of the limited‐transpiration trait and plant hydraulic conductance identified in this study offers specific candidate inbred lines that could be used as genetic resources for improving sweet corn growth and yield for well‐watered environments.
Sustainable Routes for the Synthesis of Renewable Adipic Acid from Biomass Derivatives
Authors: Lang Man , Li Hao 
Published: October 2021

AbstractAdipic acid (AA) is a key industrial dicarboxylic acid intermediate used in nylon manufacturing. Unfortunately, the traditional process technology is accompanied by serious environmental pollution. Given the growing demand for adipic acid and the desire to reduce its negative impact on the environment, considerable efforts have been devoted to developing more green and friendly routes. This Review is focused on the latest advances in the sustainable preparation of AA from biomass‐based platform molecules, including 5‐hydroxymethylfufural, glucose, γ‐valerolactone, and phenolic compounds, through biocatalysis, chemocatalysis, and the combination of both. Additionally, the development of state‐of‐the‐art catalysts for different catalytic systems systematically is discussed and summarized, as well as their reaction mechanisms. Finally, the prospects for all preparation routes are critically evaluated and key technical challenges in the development of green and sustainable processes for the manufacture of AA are highlighted. It is hoped that the green adipic acid synthesis pathways presented can provide insights and guidance for further research into other industrial processes for the production of nylon precursors in the future.
Quasi‐Parallel NiFe Layered Double Hydroxide Nanosheet Arrays for Large‐Current‐Density Oxygen Evolution Electrocatalysis
Authors: Ye Qinglan , Li Lingfeng , Li Hangyang , Gu Xiangyang , Han Boming , Xu Xuetang , Wang Fan , Li Bin 
Published: October 2021

AbstractDesigning advanced electrocatalysts for oxygen evolution at large current density (>500 mA cm−2) is critical to practical water splitting applications. Herein, a novel quasi‐parallel NiFe layered double hydroxide (NiFe LDH) nanosheet arrays with pattern alignment on Ni foam was developed. The initial α‐Ni(OH)2 layer induced effective coprecipitation between Ni2+ and Fe3+ for the formation of LDH phase, guaranteeing the electronic pulling effect among metal cations and enhancing the interaction between active materials and substrate for excellent adhesion and electrical conductivity. Quasi‐parallel NiFe LDH nanoarrays exhibited outstanding oxygen evolution activity with a small Tafel slope of 30.1 mV dec−1 and overpotentials of 196, 255, and 284 mV at a current density of 10, 500, and 1000 mA cm−2 in 1.0 m KOH solution, respectively, and high stability over 40 h at 750 mA cm−2. This work presents a new strategy towards fabricating electrode materials with exceptional performance.
A novel method to standardise serum IgA measurements shows an increased prevalence of IgA deficiency in young children with recurrent respiratory tract infections
Authors: Koenen Mischa H , Bosma Madeleen , Roorda Udo A , Wopereis Fabiënne MY , Roos Anja , van der Vries Erhard , Bogaert Debby , Sanders Elisabeth AM , Boes Marianne , Heidema Jojanneke , van Montfrans Joris M , Balemans Walter AF , van Holten Thijs C , Verhagen Lilly M 
Published: October 2021

AbstractObjectivesWhile physicians are often confronted with immunoglobulin A (IgA) deficiency in children with recurrent infections, the clinical relevance of this finding is unclear. Large‐scale studies examining the significance of IgA deficiency in children are hampered by differences in techniques for measuring IgA and the physiological increase of IgA with age. Both result in a variety of reference values used for diagnosing IgA deficiency. We propose a new laboratory‐independent method to accurately compare IgA measurements in children of varying ages.MethodsWe present a method to standardise IgA values for age and laboratory differences. We applied this method to a multicentre case–control study of children under the age of seven suffering from recurrent respiratory tract infections (rRTI, cases) and children who had IgA measured as part of coeliac disease screening (controls). We defined IgA deficiency as serum IgA measurements < 2.5% for age‐specific reference values.ResultsWe developed reference values for IgA for seven age groups and five different laboratory assays. Using these reference values, IgA measurements from 417 cases and 224 controls were standardised to compare groups. In children aged 2 years and older, IgA deficiency was observed in 2.9% (7/242) of cases and 0% (0/189) of controls (P = 0.02).ConclusionWe present a method to compare IgA values in cohorts that vary in age and laboratory assay. This way, we showed that IgA deficiency was more prevalent in children with rRTI compared with controls. This implicates that IgA deficiency may be a clinically relevant condition, even in young children.
The role of olfactory cues in mother–pup, groupmate, and sex recognition of lesser flat‐headed bats, Tylonycteris pachypus
Authors: Liang Jie , Yang Jian , Chen Yi , Zhang Libiao 
Published: October 2021

AbstractTylonycteris pachypus is a gregarious bat species with tens of individuals in a colony. The mechanisms by which mother bats recognize their pups and adult bats recognize each other are not clear. We hypothesized that such recognition is achieved by chemical discrimination and performed experiments to test the hypothesis. Results showed that mother bats were much more attracted to the scent from their own pups. For adult bats, females were attracted to the scent from both male and female groupmates but had a higher preference to the scent from female than from male groupmates. Male bats were much more attracted to the scent from male groupmates while showed no preference to the scent from female groupmates. Within a group, both female and male bats had no difference in preference to the scent from the same or opposite sex. These results suggest that mother–pup and groupmate recognition of T. pachypus can be achieved by olfactory cues.
Plant–herbivore interactions: Combined effect of groundwater level, root vole grazing, and sedge silicification
Authors: Borowski Zbigniew , Zub Karol , Sulwiński Marcin , Suska‐Malawska Małgorzata , Konarzewski Marek 
Published: October 2021

Abstract

Accumulation of silica (Si) by plants can be driven by (1) herbivory pressure (and therefore plant–herbivore interactions), (2) geohydrological cycles, or (3) a combination of (1) and (2), with (1–3) possibly affecting Si concentration with a 1‐year delay.

To identify the relative significance of (1–3), we analyzed the concentration of Si in fibrous tussock sedge (Carex appropinquata), the population density of the root vole (Microtus oeconomus), and the groundwater level, over 11 years.

The largest influence of autumn Si concentration in leaves (Sileaf) was on the level of the current‐year groundwater table, which was positive and accounted for 13.3% of its variance. The previous year's vole population density was weakly positively correlated with Sileaf, and it alone explained 9.5% of its variance.

The only variable found to have a positive, significant effect on autumn Si concentration in rhizomes (Sirhiz) was the current‐year spring water level, explaining as much as 60.9% of its variance.

We conclude that the changes in Si concentration in fibrous tussock sedge are predominantly driven by hydrology, with vole population dynamics being secondary.

Our results provide only partial support for the existence of plant–herbivore interactions, as we did not detect the significant effects of Si tussock concentration on the vole density dynamics. This was mainly due to the low level of silicification of sedges, which was insufficient to impinge herbivores.

Future studies on plant–herbivore interactions should therefore aim at disentangling whether anti‐herbivore protection is dependent on threshold values of herbivore population dynamics. Furthermore, studies on Si accumulation should focus on the effect of water‐mediated Si availability.